ok, i was doing my hw and i just do not have a clue how to solve this.

the problem is:

(2x^3-x)cos(1-x^2)

and this is what i got or attempted so far. i'm not even sure if this is the right way. can somebody tell me where i went wrong?

[d/dx(2x^3-x)cos)1-x^2) x (2x^3-x)[d/dx(cos(1-x^2))]

=(6x^2-1)cos(1-x^2) x 2x(2x^3-x)sin(1-x^2)

thanks much!