If the line y cos alpha = xsin alpha + acos a | vedclass

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Question

(b) The tangent is $y$ $\cos \alpha = x\sin \alpha + a\cos \alpha $

$ \Rightarrow y = x	an \alpha + a$

It is a tangent to the circle ${x^2} + {

Vedclass · Accepted Answer

${\cos ^2}\alpha = 1$

Vedclass · Answer

(b) The tangent is $y$ $\cos \alpha = x\sin \alpha + a\cos \alpha $

$ \Rightarrow y = x	an \alpha + a$

It is a tangent to the circle ${x^2} + {y^2} = {a^2}$, if

${a^2} = {a^2}(1 + {	an ^2}\alpha ) $

$\Rightarrow {\sec ^2}\alpha = 1 $

$\Rightarrow {\cos ^2}\alpha = 1$.

If the line $y$ $\cos \alpha = x\sin \alpha + a\cos \alpha $ be a tangent to the circle ${x^2} + {y^2} = {a^2}$, then

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