Posted by **jnky** on Tuesday, March 18, 2014 at 11:39pm.

x^2cosx-2xsinx-2cosx

- derivatives -
**Reiny**, Wednesday, March 19, 2014 at 12:00am
I assume that you want the derivative, since you titles your post that way.

if y = x^2cosx-2xsinx-2cosx

dy/dx = (x^2)(-sinx) + 2x cosx - 2x(-cosx) - 2sinx + 2sinx

= -x^2( sinx) + 4x( cosx)

etc if needed

- derivatives - oops -
**Steve**, Wednesday, March 19, 2014 at 5:53am
d/dx sinx = cosx

- derivatives -
**Reiny**, Wednesday, March 19, 2014 at 7:36am
yup!

sloppiness on my part

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