# Math Help - Simplifying a trig expression

1. ## Simplifying a trig expression

[(1 / (cos^2 (x)) - x]*sin(x)

Can someone help me simplify this? Thanks,

Kim

2. Probably not. Why do you think it possible?

3. Originally Posted by Kim Nu
[(1 / (cos^2 (x)) - x]*sin(x)

Can someone help me simplify this? Thanks,

Kim
You've done a good job trying to line the brackets up, but they are unfortunately not correct. The "(" to the left of the "1" is never closed.

4. Originally Posted by Kim Nu
[(1 / (cos^2 (x)) - x]*sin(x)

Can someone help me simplify this? Thanks,

Kim
I cannot see any simplification other than

$\bigg[\frac{1}{\cos^2(x)}-x\bigg]\cdot\sin(x)=\frac{\sin(x)}{\cos^2(x)}-x\cdot\sin(x)=\tan(x)\cdot\sec(x)-x\cdot\sin(x)$