For the last one, -cos(2x) is my answer but it’s wrong and this what my teacher said.. The first two are correct, but in the last one, it does not want "double" angle 2x. Use double angle identities...

For the last one, -cos(2x) is my answer but it’s wrong and this what my teacher said.. The first two are correct, but in the last one, it does not want "double" angle 2x. Use double angle identities for - cos(2x) to write it in single angle x.


Extracted text: Use identities to simplify each expression. sec2 (x) 1- tan (x) cos x) = -cot^2(x) %3D sin(r) + = csc(x) %3D sin(x) sin (x) – cos (x) = | %3D