SOLUTION: Prove that sin^2 x + cos^2 x=1

SOLUTION: Prove that sin^2 x + cos^2 x=1

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Question 1027996: Prove that sin^2 x + cos^2 x=1
Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
For any angle of a right triangle, let be the adjacent side of the angle and be the opposite side of the angle and be the hypotenuse of the triangle.
From the Pythagorean theorem,

But you also know from trigonometry,

So then continuing from the equation above,

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