Question

Cos^2a(3-4 cos^2a)^2+sin^2a(3-4sin^2a)^2 is equal to

Answer 1

Hope it helps..............
:)

Answer 2

Answer:

It's value is equal to 1 ( one ) .

Step-by-step explanation:

Given , we have ;

=) cos²A ( 3 – 4 cos²A )² + sin²A ( 3 – 4 sin²A )²

=) [ cosA ( 3 – 4 cos²A ) ]² + [ sinA ( 3 – 4sin²A ) ]²

=) ( 3cosA – 4 cos³A )² + ( 3sinA – 4sin³A )²

We know that ,

3 cosA – 4cos³A = –cos 3A and

3 sinA – 4 sin³A = sin 3A

Hence , the expression becomes ;

=) ( – cos3A )² + ( sin3A )²

=) cos²3A + sin²3A

=) 1