How do I prove this equation is an identity? sin^3+sin(x)cos^2(x)/cos(x)=tan(x)

1 Answer
Mar 18, 2018

Verified below

Explanation:

(sin^3x+sin(x)cos^2(x))/cos(x)=tan(x)

GCF:
(sinx(sin^2x+cos^2x))/cos(x)=tan(x)

Apply the pythagorean identity:
sin^2x+cos^2x=1

Therefore:
(sinx(1))/cos(x)=tan(x)
sinx/cosx=tan(x)

Apply the quotient identity:
sinx/cosx= tanx

Therefore:
tanx=tanx