Verify the Trigonometric Function:
(cosx - sinx)(cosx + sinx) = 1 - 2sin^2x
(cosx - sinx)(cosx + sinx) = 1 - 2sin^2x
-
cos^2 - sin^2 =
1 - sin^2 - sin^2 =
1 - 2sin^2 =
1 - sin^2 - sin^2 =
1 - 2sin^2 =
-
LHS = cos²x – sin²x = (1 – sin²x) – sin²x = 1 – 2sin²x