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#