Answer
$sin^2(\theta)+cos^2(\theta)=1$, $tan^2(\theta)+1=sec^2(\theta)$, $cot^2(\theta)+1=csc^2(\theta)$.
Work Step by Step
The identities are the following: $sin^2(\theta)+cos^2(\theta)=1$, $tan^2(\theta)+1=sec^2(\theta)$, $cot^2(\theta)+1=csc^2(\theta)$.
