Question

Simplify the expression.
tan(-x) cos(-x) =

Answer 1

since
cos(-x) = cos (x)
tan(-x) = - tan(x)
now just solve the equation by just putting these terms
it would be
- tan(x) cos(x)

Answer 2

\[\tan(-x) = - \tan(x)\]
\[\cos(-x) = cosx\]
\[= \left( -\frac{ \sin(x) }{ \cos(x) } \right)\cos(x) = - \sin(x)\]

Answer 3

Because tanx is an odd function as is sinx.