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The pole of the straight line \( \Large x+2y=1 \) with respect to the circle \( \Large x^{2}+y^{2}=5 \) is:


A) \( \Large \left(5,\ 5\right) \)

B) \( \Large \left(5,\ 10\right) \)

C) \( \Large \left(10,\ 5\right) \)

D) \( \Large \left(10,\ 10\right) \)

Correct Answer:
B) \( \Large \left(5,\ 10\right) \)

Description for Correct answer:

Let the pole be \( \Large  \left(x_{1} ,y_{1}\right)  \) then the equation of polar with respect to the circle \( \Large x^{2} + y^{2} = 5 \) is

\( \Large xx_{1} + yy_{1} = 5 \) .. (i)

Eq (i) and x + 2y = 1 represents the same straight line

=> \( \Large x_{1} = 5,  y_{1} = 10 \)

Pole is (5,10)


Part of solved Circles questions and answers : >> Elementary Mathematics >> Circles




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