How do you simplify tan(-x)cos(-x)?

2 Answers
Deepak G.
Jul 25, 2016

-sinx

Explanation:

tan(-x)cos(-x)
=sin(-x)/cos(-x)cos(-x)
=sin(-x)
-sinx

Jim G.
Jul 25, 2016

-sinx

Explanation:

color(orange)"Reminders"

color(red)(|bar(ul(color(white)(a/a)color(black)(tanx=(sinx)/(cosx))color(white)(a/a)|))) and color(red)(|bar(ul(color(white)(a/a)color(black)(sin(-x)=-sinx)color(white)(a/a)|)))

rArrtan(-x)cos(-x)=(sin(-x))/(cancel(cos(-x)))xxcancel(cos(-x))

=sin(-x)=-sinx

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