Quote (GSW @ 22 Mar 2018 12:46)
I need some help.
Simplify the trigonometric expression. Please
sin^4 (α) − cos^4 (α) + cos^2 (α)
replaced with x because I don't have that symbol
sin^4(x) - cos^4(x) + cos^2(x)
sin^4(x) + cos^2(x)[1 - cos^2(x)]
sin^4(x) + cos^2(x)[sin^2(x)]
sin^2(x)[sin^2(x) + cos^2(x)]
sin^2(x)[1]
sin^2(x)