Question

prove cos^4 theta-cos^2 theta=sin^4∅-sin^2∅​

Answer 1

Answer:

Step-by-step explanation:

You must know that cos^2theta is equal to 1-sin^2 theta

And sin^2theta is equal to 1-cos^2 theta

LHS

cos^4 theta-cos^2 theta

cos^2 theta(cos^2 theta-1)

cos^2 theta(1-sin^2 theta-1)

cos^2 theta(-sin^2 theta)

1-sin^2 theta(-sin^2 theta)

-sin^2 theta+sin^4 theta

sin^4 theta-sin^2 theta

=RHS