A silver wire has a mass $$(0.6 \pm 0.006)$$ g, radius $$(0.5 \pm 0.005)$$ mm and length $$(4 \pm 0.04)$$ cm. The maximum percentage error in the measurement of its density will be
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A silver wire has a mass $$(0.6 \pm 0.006)$$ g, radius $$(0.5 \pm 0.005)$$ mm and length $$(4 \pm 0.04)$$ cm. The maximum percentage error in the measurement of its density will be
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A projectile is launched at an angle $$\alpha$$ with the horizontal with a velocity $$20$$ m s$$^{-1}$$. After $$10$$ s, its inclination with horizontal is $$\beta$$. The value of $$\tan\beta$$ will be : $$(g = 10$$ m s$$^{-2})$$.
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A girl standing on road holds her umbrella at $$45°$$ with the vertical to keep the rain away. If she starts running without umbrella with a speed of $$15\sqrt{2}$$ km h$$^{-1}$$, the rain drops hit her head vertically. The speed of rain drops with respect to the moving girl is
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A system of two blocks of masses $$m = 2$$ kg and $$M = 8$$ kg is placed on a smooth table as shown in figure. The coefficient of static friction between two blocks is $$0.5$$. The maximum horizontal force $$F$$ that can be applied to the block of mass $$M$$ so that the blocks move together will be $$(g = 9.8$$ m s$$^{-2})$$

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Two blocks of masses $$10$$ kg and $$30$$ kg are placed on the same straight line with coordinates $$(0, 0)$$ cm and $$(x, 0)$$ cm respectively. The block of $$10$$ kg is moved on the same line through a distance of $$6$$ cm towards the other block. The distance through which the block of $$30$$ kg must be moved to keep the position of centre of mass of the system unchanged is
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What percentage of kinetic energy of a moving particle is transferred to a stationary particle when it strikes the stationary particle of $$5$$ times its mass?
(Assume the collision to be head-on elastic collision)
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Statement I : The law of gravitation holds good for any pair of bodies in the universe.
Statement II : The weight of any person becomes zero when the person is at the centre of the earth.
In the light of the above statements, choose the correct answer from the options given below.
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The velocity of a small ball of mass $$m$$ and density $$d_1$$, when dropped in a container filled with glycerine, becomes constant after some time. If the density of glycerine is $$d_2$$, then the viscous force acting on the ball will be
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A mixture of hydrogen and oxygen has volume $$2000$$ cm$$^3$$, temperature $$300$$ K, pressure $$100$$ kPa and mass $$0.76$$ g. The ratio of number of moles of hydrogen to number of moles of oxygen in the mixture will be
[Take gas constant $$R = 8.3$$ J K$$^{-1}$$ mol$$^{-1}$$]
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The displacement of simple harmonic oscillator after $$3$$ seconds starting from its mean position is equal to half of its amplitude. The time period of harmonic motion is
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An observer moves towards a stationary source of sound with a velocity one-fifth of the velocity of sound. The percentage change in the apparent frequency is
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A force of $$10$$ N acts on a charged particle placed between two plates of a charged capacitor. If one plate of capacitor is removed, then the force acting on that particle will be.
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A $$72$$ $$\Omega$$ galvanometer is shunted by a resistance of $$8$$ $$\Omega$$. The percentage of the total current which passes through the galvanometer is
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The susceptibility of a paramagnetic material is $$99$$. The permeability of the material in Wb/A - m, is
[Permeability of free space $$\mu_0 = 4\pi \times 10^{-7}$$ Wb/A - m]
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The current flowing through an ac circuit is given by $$I = 5\sin(120\pi t)$$ A. How long will the current take to reach the peak value starting from zero?
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Match List - I with List - II
| List-I | List-II |
|---|---|
| (a) Ultraviolet rays | (i) Study crystal structure |
| (b) Microwaves | (ii) Greenhouse effect |
| (c) Infrared waves | (iii) Sterilizing surgical instrument |
| (d) X-rays | (iv) Radar system |
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Consider a light ray travelling in air is incident into a medium of refractive index $$\sqrt{2n}$$. The incident angle is twice that of refracting angle. Then, the angle of incidence will be
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An $$\alpha$$ particle and a carbon 12 atom has same kinetic energy $$K$$. The ratio of their de-Broglie wavelengths $$(\lambda_\alpha : \lambda_{C12})$$ is
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A hydrogen atom in its ground state absorbs $$10.2$$ eV of energy. The angular momentum of electron of the hydrogen atom will increase by the value of (Given, Planck's constant $$= 6.6 \times 10^{-34}$$ Js).
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Identify the correct Logic Gate for the following output ($$Y$$) of two inputs $$A$$ and $$B$$.

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A pendulum of length $$2$$ m consists of a wooden bob of mass $$50$$ g. A bullet of mass $$75$$ g is fired towards the stationary bob with a speed $$v$$. The bullet emerges out of the bob with a speed $$\frac{v}{3}$$ and the bob just completes the vertical circle. The value of $$v$$ is ______ m s$$^{-1}$$
(if $$g = 10$$ m s$$^{-2}$$).
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The area of cross-section of a large tank is $$0.5$$ m$$^2$$. It has a narrow opening near the bottom having area of cross-section $$1$$ cm$$^2$$. A load of $$25$$ kg is applied on the water at the top in the tank. Neglecting the speed of water in the tank, the velocity of the water, coming out of the opening at the time when the height of water level in the tank is $$40$$ cm above the bottom, will be ______ cm s$$^{-1}$$.
[Take $$g = 10$$ m s$$^{-2}$$]
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In a carnot engine, the temperature of reservoir is $$527°$$C and that of sink is $$200$$ K. If the work done by the engine when it transfers heat from reservoir to sink is $$12000$$ kJ, the quantity of heat absorbed by the engine from reservoir is ______ $$\times 10^6$$ J.
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A capacitor of capacitance $$50$$ pF is charged by $$100$$ V source. It is then connected to another uncharged identical capacitor. Electrostatic energy loss in the process is ______ nJ.
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A $$220$$ V, $$50$$ Hz AC source is connected to a $$25$$ V, $$5$$ W lamp and an additional resistance $$R$$ in series (as shown in figure) to run the lamp at its peak brightness, then the value of $$R$$ (in ohm) will be

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A cell, shunted by a $$8$$ $$\Omega$$ resistance, is balanced across a potentiometer wire of length $$3$$ m. The balancing length is $$2$$ m when the cell is shunted by $$4$$ $$\Omega$$ resistance. The value of internal resistance of the cell will be ______ $$\Omega$$.
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The current density in a cylindrical wire of radius $$4$$ mm is $$4 \times 10^6$$ A m$$^{-2}$$. The current through the outer portion of the wire between radial distances $$\frac{R}{2}$$ and $$R$$ is ______ $$\pi$$ A.
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In Young's double slit experiment the two slits are $$0.6$$ mm distance apart. Interference pattern is observed on a screen at a distance $$80$$ cm from the slits. The first dark fringe is observed on the screen directly opposite to one of the slits. The wavelength of light will be ______ nm.
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A beam of monochromatic light is used to excite the electron in $$Li^{++}$$ from the first orbit to the third orbit. The wavelength of monochromatic light is found to be $$x \times 10^{-10}$$ m. The value of $$x$$ is ______.
[Given $$hc = 1242$$ eV nm]
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The height of a transmitting antenna at the top of a tower is $$25$$ m and that of receiving antenna is, $$49$$ m. The maximum distance between them, for satisfactory communication in LOS (Line-Of-Sight) is $$K\sqrt{5} \times 10^2$$ m. The value of $$K$$ is ______.
(Assume radius of Earth is $$64 \times 10^5$$ m) [Calculate upto nearest integer value]
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Given below are two statements : one is labelled as Assertion and the other is labelled as Reason.
Assertion: The ionic radii of $$O^{2-}$$ and $$Mg^{2+}$$ are same.
Reason: Both $$O^{2-}$$ and $$Mg^{2+}$$ are isoelectronic species.
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Based upon VSEPR theory, match the shape (geometry) of the molecules in List-I with the molecules in List-II
| List-I (Shape) | List-II (Molecules) |
|---|---|
| A T-shaped | I. $$XeF_4$$ |
| B Trigonal planar | II. $$SF_4$$ |
| C Square planar | III. $$ClF_3$$ |
| D See-saw | IV. $$BF_3$$ |
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Match List - I with List - II.
| List-I | List-II |
|---|---|
| (A) Spontaneous process | (I) $$\Delta H < 0$$ |
| (B) Process with $$\Delta P = 0, \Delta T = 0$$ | (II) $$\Delta G_{T,P} < 0$$ |
| (C) $$\Delta H_{reaction}$$ | (III) Isothermal and isobaric process |
| (D) Exothermic Process | (IV) [Bond energies in reactants] - [Bond energies in products] |
Choose the correct answer from the options given below
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Addition of $$H_2SO_4$$ to $$BaO_2$$ produces
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$$BeCl_2$$ reacts with $$LiAlH_4$$ to give
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Match List - I with List - II.
| List-I (Si-Compounds) | List-II (Si-Polymeric/Other Products) |
|---|---|
| A $$(CH_3)_4Si$$ | I Chain Silicone |
| B $$(CH_3)Si(OH)_3$$ | II Dimeric Silicone |
| C $$(CH_3)_2Si(OH)_2$$ | III Silane |
| D $$(CH_3)_3Si(OH)$$ | IV 2D-Silicone |
Choose the correct answer from the options given below
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L-isomer of a compound 'A'($$C_4H_8O_4$$) gives a positive test with $$[Ag(NH_3)_2]^+$$. Treatment of 'A' with acetic anhydride yields triacetate derivative. Compound 'A' produces an optically active compound (B) and an optically inactive compound (C) on treatment with bromine water and $$HNO_3$$ respectively. Compound (A) is :
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Given below are two Statements :
Statement I : Classical smog occurs in cool humid climate. It is a reducing mixture of smoke, fog and sulphur dioxide.
Statement II : Photochemical smog has components, ozone, nitric oxide, acrolein, formaldehyde, PAN etc.
In the light of the above statements, choose the most appropriate answer from the options given below.
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Given below are two statements : one is labelled as Assertion and the other is labelled as Reason.
Assertion: At $$10°$$C, the density of a $$5$$ M solution of KCl [atomic masses of K & Cl are $$39$$ & $$35.5$$ g mol$$^{-1}$$ respectively], is 'x' g mL$$^{-1}$$. The solution is cooled to $$-21°$$C. The molality of the solution will remain unchanged.
Reason: The molality of a solution does not change with temperature as mass remains unaffected with temperature.
In the light of the above statements, choose the most appropriate answer from the options given below.
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Match List - I with List - II.
| List-I | List-II |
|---|---|
| A Lyophilic colloid | I Liquid-liquid colloid |
| B Emulsion | II Protective colloid |
| C Positively charged colloid | III $$FeCl_3 + NaOH$$ |
| D Negatively charged colloid | IV $$FeCl_3$$ + hot water |
Choose the correct answer from the options given below
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Match List - I with List - II.
| List-I | List-II |
|---|---|
| A Concentration of gold ore | I Aniline |
| B Leaching of alumina | II NaOH |
| C Froth stabiliser | III $$SO_2$$ |
| D Blister copper | IV NaCN |
Choose the correct answer from the options given below
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Heating white phosphorus with conc. NaOH solution gives mainly
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Which of the following will have maximum stabilization due to crystal field?
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The major product of the following reaction is

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Which of the following reactions will yield benzaldehyde as a product?

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'A' and 'B' respectively are
A $$\xrightarrow[(2) Zn-H_2O]{(1) O_3 \atop}$$ Ethane-1,2-dicarbaldehyde + Glyoxal/Oxaldehyde
B $$\xrightarrow[(2) Zn-H_2O]{(1) O_3 \atop}$$ 5-oxohexanal
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Given below are two statements :
Statement - I : In Hofmann degradation reaction, the migration of only an alkyl group takes place from carbonyl carbon of the amide to the nitrogen atom.
Statement - II : The group is migrated in Hofmann degradation reaction to electron deficient atom.
In the light of the above statements, choose the most appropriate answer from the options given below
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Match List - I with List - II.
| List-I (Polymer) | List-II (Used in) |
|---|---|
| A Bakelite | I Radio and television cabinets |
| B Glyptal | II Electrical switches |
| C PVC | III Paints and Lacquers |
| D Polystyrene | IV Water pipes |
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Match List - I with List - II.
Choose the correct answer from the options given below
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Which of the following is structure of a separating funnel?
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If the uncertainty in velocity and position of a minute particle in space are, $$2.4 \times 10^{-26}$$ (ms$$^{-1}$$) and $$10^{-7}$$ (m) respectively. The mass of the particle in g is ______ (Nearest integer)
(Given : $$h = 6.626 \times 10^{-34}$$ Js)
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$$2NOCl(g) \rightleftharpoons 2NO(g) + Cl_2(g)$$
In an experiment, $$2.0$$ moles of NOCl was placed in a one-litre flask and the concentration of NO after equilibrium established, was found to be $$0.4$$ mol/L. The equilibrium constant at $$30°$$C is ______ $$\times 10^{-4}$$.
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Total number of possible stereoisomers of dimethyl cyclopentane is ______
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Metal deficiency defect is shown by $$Fe_{0.93}O$$. In the crystal, some $$Fe^{2+}$$ cations are missing and loss of positive charge is compensated by the presence of $$Fe^{3+}$$ ions. The percentage of $$Fe^{2+}$$ ions in the $$Fe_{0.93}O$$ crystals is ______ (Nearest integer)
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Two elements A and B which form $$0.15$$ moles of $$A_2B$$ and $$AB_3$$ type compounds. If both $$A_2B$$ and $$AB_3$$ weigh equally, then the atomic weight of A is ______ times of atomic weight of B.
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$$2$$ g of a non-volatile non-electrolyte solute is dissolved in $$200$$ g of two different solvents A and B whose ebullioscopic constants are in the ratio of $$1 : 8$$. The elevation in boiling points of A and B are in the ratio $$\frac{x}{y}$$ ($$x : y$$). The value of $$y$$ is ______ (Nearest Integer)
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The limiting molar conductivities of NaI, $$NaNO_3$$ and $$AgNO_3$$ are $$12.7, 12.0$$ and $$13.3$$ mS m$$^2$$ mol$$^{-1}$$, respectively (all at $$25°$$C). The limiting molar conductivity of AgI at this temperature is ______ mS m$$^2$$ mol$$^{-1}$$.
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The rate constant for a first order reaction is given by the following equation :
$$\ln k = 33.24 - \frac{2.0 \times 10^4 K}{T}$$
The Activation energy for the reaction is given by ______ kJ mol$$^{-1}$$. (In Nearest integer) (Given : $$R = 8.3$$ J K$$^{-1}$$ mol$$^{-1}$$)
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The number of statement(s) correct from the following for Copper is/are
(A) Cu(II) complexes are always paramagnetic
(B) Cu(I) complexes are generally colourless
(C) Cu(I) is easily oxidized
(D) In Fehling solution, the active reagent has Cu(I)
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Acidified potassium permanganate solution oxidises oxalic acid. The spin-only magnetic moment of the mangenese product formed from the above reaction is ______ B.M. (Nearest Integer)
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The area of the polygon, whose vertices are the non-real roots of the equation $$\bar{z} = iz^2$$ is
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If $$x = \sum_{n=0}^{\infty} a^n, y = \sum_{n=0}^{\infty} b^n, z = \sum_{n=0}^{\infty} c^n$$, where $$a, b, c$$ are in A.P. and $$|a| < 1, |b| < 1, |c| < 1, abc \neq 0$$, then
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The value of $$\cos\left(\frac{2\pi}{7}\right) + \cos\left(\frac{4\pi}{7}\right) + \cos\left(\frac{6\pi}{7}\right)$$ is equal to
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In an isosceles triangle $$ABC$$, the vertex $$A$$ is $$(6, 1)$$ and the equation of the base $$BC$$ is $$2x + y = 4$$. Let the point $$B$$ lie on the line $$x + 3y = 7$$. If $$(\alpha, \beta)$$ is the centroid of $$\triangle ABC$$, then $$15(\alpha + \beta)$$ is equal to
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Let the eccentricity of an ellipse $$\frac{x^2}{a^2} + \frac{y^2}{b^2} = 1, a > b$$, be $$\frac{1}{4}$$. If this ellipse passes through the point $$\left(-4\sqrt{\frac{2}{5}}, 3\right)$$, then $$a^2 + b^2$$ is equal to
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Let $$a$$ be an integer such that $$\lim_{x \to 7} \frac{18 - [1-x]}{[x-3a]}$$ exists, where $$[t]$$ is greatest integer $$\leq t$$. Then $$a$$ is equal to
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The boolean expression $$(\sim(p \wedge q)) \vee q$$ is equivalent to
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Let the system of linear equations $$x + 2y + z = 2, \alpha x + 3y - z = \alpha, -\alpha x + y + 2z = -\alpha$$ be inconsistent. Then $$\alpha$$ is equal to
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$$\sin^{-1}\left(\sin\frac{2\pi}{3}\right) + \cos^{-1}\left(\cos\frac{7\pi}{6}\right) + \tan^{-1}\left(\tan\frac{3\pi}{4}\right)$$ is equal to
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If $$\cos^{-1}\left(\frac{y}{2}\right) = \log_e\left(\frac{x}{5}\right)^5, |y| < 2$$, then
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The number of distinct real roots of $$x^4 - 4x + 1 = 0$$ is
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The lengths of the sides of a triangle are $$10 + x^2, 10 + x^2$$ and $$20 - 2x^2$$. If for $$x = k$$, the area of the triangle is maximum, then $$3k^2$$ is equal to
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$$\int \frac{(x^2+1)e^x}{(x+1)^2} dx = f(x)e^x + C$$, where $$C$$ is a constant, then $$\frac{d^3f}{dx^3}$$ at $$x = 1$$ is equal to
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The value of the integral $$\int_{-2}^{2} \frac{|x^3+x|}{(e^{x|x|}+1)} dx$$ is equal to
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Let $$\frac{dy}{dx} = \frac{ax - by + a}{bx + cy + a}$$, where $$a, b, c$$ are constants, represent a circle passing through the point $$(2, 5)$$. Then the shortest distance of the point $$(11, 6)$$ from this circle is
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If $$\frac{dy}{dx} + \frac{2^{x-y}(2^y-1)}{2^x - 1} = 0, x, y > 0, y(1) = 1$$, then $$y(2)$$ is equal to
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Let $$\vec{a} = \hat{i} + \hat{j} - \hat{k}$$ and $$\vec{c} = 2\hat{i} - 3\hat{j} + 2\hat{k}$$. Then the number of vectors $$\vec{b}$$ such that $$\vec{b} \times \vec{c} = \vec{a}$$ and $$|\vec{b}| \in \{1, 2, \ldots, 10\}$$ is
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If two straight lines whose direction cosines are given by the relations $$l + m - n = 0, 3l^2 + m^2 + cnl = 0$$ are parallel, then the positive value of $$c$$ is
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Five numbers $$x_1, x_2, x_3, x_4, x_5$$ are randomly selected from the numbers $$1, 2, 3, \ldots, 18$$ and are arranged in the increasing order $$(x_1 < x_2 < x_3 < x_4 < x_5)$$. The probability that $$x_2 = 7$$ and $$x_4 = 11$$ is
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Let $$X$$ be a random variable having binomial distribution $$B(7, p)$$. If $$P(X = 3) = 5P(X = 4)$$, then the sum of the mean and the variance of $$X$$ is
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The number of ways, 16 identical cubes, of which 11 are blue and rest are red, can be placed in a row so that between any two red cubes there should be at least 2 blue cubes, is ______
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If the sum of the first ten terms of the series $$\frac{1}{5} + \frac{2}{65} + \frac{3}{325} + \frac{4}{1025} + \frac{5}{2501} + \ldots$$ is $$\frac{m}{n}$$, where $$m$$ and $$n$$ are co-prime numbers, then $$m + n$$ is equal to ______
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If the coefficient of $$x^{10}$$ in the binomial expansion of $$\left(\frac{\sqrt{x}}{5^{1/4}} + \frac{\sqrt{5}}{x^{1/3}}\right)^{60}$$ is $$5^k l$$, where $$l, k \in N$$ and $$l$$ is coprime to $$5$$, then $$k$$ is equal to ______
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A rectangle $$R$$ with end points of the one of its sides as $$(1, 2)$$ and $$(3, 6)$$ is inscribed in a circle. If the equation of a diameter of the circle is $$2x - y + 4 = 0$$, then the area of $$R$$ is ______
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A circle of radius $$2$$ unit passes through the vertex and the focus of the parabola $$y^2 = 2x$$ and touches the parabola $$y = \left(x - \frac{1}{4}\right)^2 + \alpha$$, where $$\alpha > 0$$. Then $$(4\alpha - 8)^2$$ is equal to ______
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The positive value of the determinant of the matrix $$A$$, whose $$Adj(Adj(A)) = \begin{bmatrix} 14 & 28 & -14 \\ -14 & 14 & 28 \\ 28 & -14 & 14 \end{bmatrix}$$, is ______
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Let $$f : R \to R$$ be a function defined $$f(x) = \frac{2e^{2x}}{e^{2x}+e}$$. Then $$f\left(\frac{1}{100}\right) + f\left(\frac{2}{100}\right) + f\left(\frac{3}{100}\right) + \ldots + f\left(\frac{99}{100}\right)$$ is equal to ______
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If the sum of all the roots of the equation $$e^{2x} - 11e^x - 45e^{-x} + \frac{81}{2} = 0$$ is $$\log_e P$$, then $$P$$ is equal to ______
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Let $$A_1 = \{(x,y) : |x| \leq y^2, |x| + 2y \leq 8\}$$ and $$A_2 = \{(x,y) : |x| + |y| \leq k\}$$. If $$27$$ (Area $$A_1$$) $$= 5$$ (Area $$A_2$$), then $$k$$ is equal to ______
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Let the mirror image of the point $$(a, b, c)$$ with respect to the plane $$3x - 4y + 12z + 19 = 0$$ be $$(a - 6, \beta, \gamma)$$. If $$a + b + c = 5$$, then $$7\beta - 9\gamma$$ is equal to ______
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