Question

63. If a = x cos^2 alpha + y sin^2alpha , then (x - a)(y-a) cosec^2 alpha sec^2 alpha =
1) (x - y)2
2) (x + y)?
3) - (x + y)2
4)-(x-y)2
please slove quickly​

Answer 1

Answer:

Given a=xcos

2

α+ysin

2

α

⟹x−a=x−xcos

2

α−ysin

2

α=x(1−cos

2

α)−ysin

2

α=xsin

2

α−ysin

2

α=(x−y)sin

2

α

⟹y−a=y−xcos

2

α−ysin

2

α=y(1−sin

2

α)−xcos

2

α=ycos

2

α−xcos

2

α=−(x−y)cos

2

α

(x−a)(y−a)+(x−y)

2

+sin

2

αcos

2

α=−(x−y)

2

sin

2

αcos

2

α+(x−y) Square 2sin Square 2 αcos Square 2 α=0

So the given relation is False