Join WhatsApp Icon JEE WhatsApp Group
Question 67

Let the circle $$C_1 : x^2 + y^2 - 2(x + y) + 1 = 0$$ and $$C_2$$ be a circle having centre at $$(-1, 0)$$ and radius 2. If the line of the common chord of $$C_1$$ and $$C_2$$ intersects the $$y$$-axis at the point $$P$$, then the square of the distance of $$P$$ from the centre of $$C_1$$ is :

Given $$C_1: x^2 + y^2 - 2(x+y) + 1 = 0$$ and $$C_2$$ has centre $$(-1, 0)$$ and radius 2.

We rewrite $$C_1$$ as $$ x^2 - 2x + y^2 - 2y + 1 = 0 $$ which becomes $$ (x-1)^2 - 1 + (y-1)^2 - 1 + 1 = 0 $$ and hence $$ (x-1)^2 + (y-1)^2 = 1. $$

The centre of $$C_1$$ is $$(1, 1)$$ and the radius is 1.

For $$C_2$$ with centre $$(-1,0)$$ and radius 2 the equation is $$ (x+1)^2 + y^2 = 4, $$ which expands to $$ x^2 + 2x + 1 + y^2 = 4 $$ and simplifies to $$ x^2 + y^2 + 2x - 3 = 0. $$

The common chord is obtained by subtracting the equations of $$C_2$$ from $$C_1$$: $$ (x^2 + y^2 - 2x - 2y + 1) - (x^2 + y^2 + 2x - 3) = 0, $$ giving $$ -2x - 2y + 1 - 2x + 3 = 0, $$ or $$ -4x - 2y + 4 = 0 $$ which simplifies to $$ 2x + y - 2 = 0. $$

Setting $$x=0$$ in the chord equation yields $$2(0)+y-2=0$$, so $$y=2$$, and hence $$P=(0,2)$$.

The square of the distance from $$P$$ to the centre of $$C_1$$ is $$ d^2 = (0-1)^2 + (2-1)^2 = 1 + 1 = 2. $$

The correct answer is Option (1): 2.

Get AI Help

Video Solution

video

Create a FREE account and get:

  • Free JEE Mains Previous Papers PDF
  • Take JEE Mains paper tests

JEE Quant Questions | JEE Quantitative Ability

JEE DILR Questions | LRDI Questions For JEE

JEE Verbal Ability Questions | VARC Questions For JEE

Free JEE Topicwise Questions

JEE Rotational MotionJEE Units & MeasurementsJEE Atomic StructureJEE GravitationJEE Periodic Table & PeriodicityJEE StatisticsJEE Inverse Trigonometric FunctionsJEE Magnetism & Magnetic MaterialsJEE Sequences & SeriesJEE MatricesJEE Alternating CurrentsJEE Carboxylic AcidsJEE Permutations & CombinationsJEE Work, Energy & PowerJEE Electromagnetic InductionJEE Electronic DevicesJEE d and f-Block ElementsJEE Chemical KineticsJEE Heat TransferJEE Three Dimensional GeometryJEE Magnetic Effects of CurrentJEE Hydrocarbons - AromaticJEE Electromagnetic WavesJEE Aldehydes & KetonesJEE Hydrocarbons - AlkanesJEE Applications of DerivativesJEE EquilibriumJEE Indefinite IntegrationJEE Chemical ThermodynamicsJEE ElectrochemistryJEE ProbabilityJEE BiomoleculesJEE Continuity & DifferentiabilityJEE Kinetic Theory of GasesJEE Vector AlgebraJEE Hydrocarbons - AlkynesJEE Differential EquationsJEE Current & ResistanceJEE Straight LinesJEE WavesJEE Redox ReactionsJEE Hydrocarbons - AlkenesJEE DeterminantsJEE SolutionsJEE Ray OpticsJEE Dual Nature of Matter & RadiationJEE Chemical Bonding & Molecular StructureJEE Complex NumbersJEE Sets, Relations & FunctionsJEE Electric Charges & FieldsJEE Laws of MotionJEE Fluid MechanicsJEE Basic Concepts in ChemistryJEE Trigonometric FunctionsJEE LimitsJEE Laws of ThermodynamicsJEE Kinematics - 2D MotionJEE p-Block Elements (Groups 13-18)JEE Simple Harmonic MotionJEE Electric Potential & CapacitanceJEE Coordination CompoundsJEE JEE 2D GeometryJEE CirclesJEE Definite IntegrationJEE EMF & Circuit AnalysisJEE Surface TensionJEE Atoms & NucleiJEE Laboratory Experiments - XIJEE Number SystemJEE Basic Principles of Organic ChemistryJEE Wave OpticsJEE Quadratic EquationsJEE Alcohols, Phenols & EthersJEE Organic Compounds with HalogensJEE DifferentiationJEE Conic SectionsJEE Nitrogen-Containing CompoundsJEE ElasticityJEE Practical Organic ChemistryJEE Kinematics - 1D MotionJEE Purification & CharacterisationJEE Binomial Theorem
Ask AI