SOLUTION: how do i prove the trig identity? (tan^2X)/secX = secX - cosX

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Question 405691: how do i prove the trig identity? (tan^2X)/secX = secX - cosX
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
how do i prove the trig identity? (tan^2X)/secX = secX - cosX
..
start with the left side,
tan^2/sec
=(sin2/cos^2)/(1/cos)
=sin^2/cos
=(1-cos^2)/cos
=1/cos-cos^2/cos
=sec-cos
ans:left-hand side=right-hand side