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Let $$O$$ be the origin, the point A be $$z_{1}=\sqrt{3}+2\sqrt{2}i$$, the point $$B(z_{2})$$ be such that $$\sqrt{3}|z_{2}|=|z_{1}|$$ and $$arg(z_{2})=arg(z_{1})+\frac{\pi}{6}$$. Then
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Let $$f:\mathbb{R}\rightarrow \mathbb{R}$$ be a function defined by $$f(x)=(2+3a)x^{2}+(\frac{a+2}{a-1})x+b,a\neq 1$$ If $$f(x+y)=f(x)+f(y)+1-\frac{2}{7}xy$$, then the value of $$28\sum_{i=1}^{5}|f(i)|$$ is
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Let ABCD be a trapezium whose vertices lie on the parabola $$y^{2}=4x$$. Let the sides AD and BC of the trapezium be parallel to y -axis. If the diagonal AC is of length $$\frac{25}{4}$$ and it passes through the point (1,0), then the area of ABCD is
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The sum of all local minimum values of the function
$$f(x) = \left\{\begin{array}{l l}1-2x, & \quad {x<-1}\\ \frac{1}{3}(7+2|x|), & \quad {-1\leq x\leq 2}\\\frac{11}{18}(x-4)(x-5), & \quad {x>2}\\ \end{array}\right.$$ is
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Let $$^{n}C_{r-1}=28,^{n}C_{r}=56$$ and $$^{n}C_{r+1}=70$$. Let $$A(4\cos t,4\sin t),B(2\sin t,-2\cos t)$$ and $$C(3r-n,r^{2}-n-1)$$ be the vertices of a triangle ABC, where t is a parameter. If $$(3x-1)^{2}+(3y)^{2}=\alpha$$, is the locus of the centroid of triangle ABC, then $$\alpha$$ equals
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Let the equation of the circle, which touches $$x$$-axis at the point $$(a,0),a > 0$$ and cuts off an intercept of length $$b$$ on $$y$$-axis be $$x^{2}+y^{2}-\alpha x +\beta y+\gamma =0$$. If the circle lies below x-axis, then the ordered pair $$(2a,b^{2})$$ is equal to
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If $$f(x)=\frac{2^{x}}{2^{x}+\sqrt{2}},x \in \mathbb{R}$$, then $$\sum_{k=1}^{81}f(\frac{k}{82})$$ is equals to
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Two number $$k_{1}$$ and $$k_{2}$$ are randomly chosen from the set of natural numbers. Then, the probability that the value of $$i^{k_{1}}+i^{k_{2}},(i=\sqrt{-1})$$ is non-zero, equals
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If the image of the point (4,4,3)in the line $$\frac{x-1}{2}=\frac{y-2}{1}=\frac{z-1}{3}$$ is $$(\alpha ,\beta ,\gamma)$$, then $$\alpha +\beta +\gamma$$ is equal to
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$$\cos \left(\sin^{-1}\frac{3}{5}+\sin^{-1}\frac{5}{13}+\sin^{-1}\frac{33}{65}\right)$$ is equal to:
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Let $$A(x,y,Z)$$ be a point in $$xy-plain$$,which is equidistant from three points (0, 3, 2), (2, 0, 3) and (0, 0, 1). Let B = (1, 4, −1) and C = (2, 0, −2). Then among the statements $$(SI): \triangle ABC$$ is an isosceles right angled triangle, and (SI):the area of $$\triangle ABC$$ is $$\frac{9\sqrt{2}}{2}$$,
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The area (in sq. units) of the region $$\left\{(x,y): 0\leq y\leq 2|x|+1,0\leq y\leq x^{2}+1,|x|\leq 3\right\}$$ is
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The sum of the squares of all the roots of the equation $$x^{2}+|2x-3|-4=0$$, is
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Let $$T_{r}$$ be the $$r^{th}$$ term of an A.P. If for some m,$$T_{m}=\frac{1}{25},T_{25}=\frac{1}{20}$$, and $$20\sum_{r=1}^{25}T_{r}=13$$,then $$5m\sum_{r=m}^{2m}T_{r}$$ is equal to
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Three defective oranges are accidently mixed with seven good ones and on looking at them, it is not possible to differentiate between them. Two oranges are drawn at random from the lot. If $$x$$ denote the number of defective oranges, then the variance of $$x$$ is
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Let for some function $$y=f(x),\int_{0}^{x}tf(t)dt=x^{2}f(x),x > 0$$ and $$f(2)=3$$. Then $$f(6)$$ is equal to
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If $$\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}}\frac{96x^{2}\cos^{2}x}{(1+e^{x})}dx=\pi (\alpha \pi^{2}+\beta),\alpha,\beta \in \mathbb{Z}$$,then $$(\alpha +\beta)^{2}$$ equals
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Let $$\langle a_{n}\rangle$$ be a sequence such that $$a_{0}=0,a_{1}=\frac{1}{2}$$ and $$2a_{n+2}=5a_{n+1}-3a_{n},n=0,1,2,3,....$$ Then $$\sum_{k=1}^{100}a_{k}$$ is equal to
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The number of different 5 digit numbers greater than 50000 that can be formed using the digits 0 ,1, 2, 3, 4, 5, 6, 7 (repetition allowed) such that the sum of their first and last digits should not be more than 8 , is
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The relation $$R=\left\{(x,y):x,y \in \mathbb{Z}\text{ and }x+y\text{ is even}\right\}$$ is:
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Let $$f(x) = \left\{\begin{array}{l l}3x & \quad {x<0}\\min\left\{1+x+[x],x+2[x]\right\}, & \quad {0\leq x\leq 2}\\ 5, & \quad {x>2,} \end{array}\right.$$ where [.] denotes greatest integer function. If $$\alpha$$ and $$\beta$$ are the number of points, where f is not continuous and is not differentiable, respectively, then $$\alpha +\beta$$ equals_________
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Let M denote the set of all real matrices of order $$3\times 3$$ and let$$S=\left\{-3,-2,-1,1,2\right\}$$. Let
$$S_{1}=\left\{A=[a_{ij}] \in M : A=A^{T}\text{ and }a_{ij} \in S,\forall i,j\right\},$$
$$S_{2}=\left\{A=[a_{ij}] \in M : A=-A^{T}\text{ and }a_{ij} \in S,\forall i,j\right\},$$
$$S_{3}=\left\{A=[a_{ij}] \in M : a_{11}+a_{22}+a_{33}=0\text{ and }a_{ij} \in S,\forall i,j\right\},$$
If $$n(S_{1}\cup S_{2} \cup S_{3})=125\alpha$$, then $$alpha$$ equals___________
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If $$\alpha =1+\sum_{r=1}^{6}(-3)^{r-1}$$ $$^{12}C_{2r-1}$$, then the distance of the point $$(12,\sqrt{3})$$ from the line $$\alpha x-\sqrt{3}y+1$$ is________
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Let $$E_{1}:\frac{x^{2}}{9}+\frac{y^{2}}{4}=1$$ be an ellipse. Ellipses $$E_{1}$$'s are constructed such that their centres and eccentricities are same as that of $$E_{1}$$, and the length of minor axis of $$E_{i}$$ is the length of major axis of $$E_{i+1}(i \geq 1)$$. If $$A_{i}$$ is the area of the ellipse $$E_{i}$$ then $$\frac{5}{\pi}\left(\sum_{i=1}^{\infty}A_{i}\right)$$, is equal to
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Let $$\overrightarrow{a}=\hat{i}+\hat{j}+\hat{k},\overrightarrow{b}=2\hat{i}+2\hat{j}+\hat{k}$$ and $$\overrightarrow{d}=\overrightarrow{a}\times \overrightarrow{b}$$. If$$\overrightarrow{c}$$ is a vector such that $$\overrightarrow{a}. \overrightarrow{c}=|\overrightarrow{c}|,|\overrightarrow{c}-2\overrightarrow{a}|^{2}=8$$ and the angle between $$\overrightarrow{d}$$ and $$\overrightarrow{c}$$ is $$\frac{\pi}{4}$$, then $$|10-3\overrightarrow{b}.\overrightarrow{c}|+|\overrightarrow{d}\times \overrightarrow{c}|^{2}$$ is equal to
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