Question

Verify the x value

2cos^4x-cos^2x=0

x=pi/2

Answer 1

so I know that the cos 90 degrees is just 1.

so the exponents here don't really do anything.

isn't this 2-1=1?

Answer 2

@EclipsedStar @iambatman

Answer 3

cos(90) is not 1

Answer 4

http://www.mathsisfun.com/geometry/images/circle-unit-304560.gif

Answer 5

crud

Answer 6

cos 90=0, 0-0=0, got it, thanks