trig identities

Question

+2

540

1

verify the identity of (1+sin a)(1-sin a)=cos^2a

Guest Sep 23, 2015

+130516

+5

Best Answer

(1+sin a)(1-sin a)=cos^2a expand the left side

1 - sin^'2a = cos²a add sin²a to each side

1 = sin²a + cos²a and this is always true

CPhill Sep 23, 2015

CPhill · Answer 1 · 2015-09-23T06:44:02

(1+sin a)(1-sin a)=cos^2a expand the left side

1 - sin^'2a = cos²a add sin²a to each side

1 = sin²a + cos²a and this is always true