Tuesday

May 3, 2016
Posted by **Amanda** on Tuesday, November 3, 2009 at 5:41pm.

cos^2(4x)

- Calculus (derivatives) -
**MathMate**, Tuesday, November 3, 2009 at 6:21pmUse the chain rule:

d(f(u(x))/dx=df/du.du/dx

d(cos²(4x))/dx

=2cos(4x)d(cos(4x))/dx

=2cos(4x)(-sin(4x))d(4x)/dx

=2cos(4x)(-sin(4x))(4)

=-8sin(4x)cos(4x)

=-4sin(8x)

The last simplification may not be required or recognized by a computerized answer.