(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Evaluate cos(θ + π/2) if sin θ = 3/7, exactly.

2. Relevant equations

How do I go about doing this exactly instead of approximately on the calculator?

3. The attempt at a solution

The only way I know how to do it is taking the inverse sin of 3/7 and adding 90 degrees and taking the cos of that result.

Thank you for your time!

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# Homework Help: Evaluate sin(theta)

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