The Tangents Drawn From The Origin To The Circle x2 + y2 – 2kx – 2ry + r2 = 0 Are Perpendicular, If:

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The tangents drawn from the origin to the circle x2 + y2 – 2kx – 2ry + r2 = 0 are perpendicular, if:


Correct option is

k = r

Equation of the circle is                   











∴ tangents are perpendicular coefficient of x2 + coefficient of y2 = 0  






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