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[ginomath123]

Given that sin x = 2/5 use a Pythagorean identity to find the cos x in simplest radical form.

 

[LCKurtz]

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[Dr.Peterson]

Given that sin x = 2/5 use a Pythagorean identity to find the cos x in simplest radical form.

Can you state the Pythagorean identity that involves the sine and cosine?

Then what happens if you replace sin(x) with 2/5?