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I : If (cos alpha )/(a)=(sin alpha )/(b)...

I : If `(cos alpha )/(a)=(sin alpha )/(b)` then `a cos 2 alpha + b cos 2 alpha =a `
II : If ` (sin alpha )/(a) =(cos alpha )/(b) ` then ` a sin 2 alpha + b cos 2 alpha = a `

A

Only I is true

B

Only II is true

C

Both I and II are true

D

neither I nor II are true

Text Solution

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The correct Answer is:
A
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