how do i prove (sin^4 x)-(cos^4 x)= (2sin^2x)-1

- March 21st 2010, 07:42 PMsomanyquestions[SOLVED] Verify that each trigonometric equation is an identity.
how do i prove (sin^4 x)-(cos^4 x)= (2sin^2x)-1

- March 21st 2010, 07:48 PMpickslides
- March 21st 2010, 07:51 PMsomanyquestions
- March 21st 2010, 08:05 PMStroodle

- March 21st 2010, 08:13 PMsomanyquestions
- March 21st 2010, 08:16 PMpickslides
- March 21st 2010, 08:17 PMStroodle
That works too :)