First slide

Trigonometric Identities

Question

If $a = x \cos^{2} A + y \sin^{2} A$ then $(x - a) (y - a) + {(x - y)}^{2} \sin^{2} A \cos^{2} A =$

Moderate

A

0
B

3
C

2
D

1

Solution

$x - a = x - x \cos^{2} A - y \sin^{2} A = x \sin^{2} A - y \sin^{2} A = (x - y) \sin^{2} A y - a = y - x \cos^{2} A - y \sin^{2} A = y \cos^{2} A - x \cos^{2} A = - (x - y) \cos^{2} A (x - a) (y - a) = - {(x - y)}^{2} \sin^{2} A \cos^{2} A$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App