How do you verify the identity $cot^2y(sec^2y-1)=1$ ?

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Answer 1 · 2017-01-17T20:38:01

see below

Left Hand Side:

Use identity : $1+tan^2y=sec^2y$

$cot^2y(sec^2y-1)=cot^2ytan^2y$

$=cos y/siny * siny /cos y$

$=cancelcos y/cancelsiny * cancelsiny /cancelcos y$

$=1$

$:.=$ Right Hand Side

How do you verify the identity cot^2y(sec^2y-1)=1cot^2y(sec^2y-1)=1?