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trig identites/ proofs (1 Viewer)
- Thread starter NizDiz
- Start date
Thanks guys 
Alright, from what I've read, you're trying to prove sin^2 x + cos^2 x = 1
You first have to draw a right-angle triangle. A hypotenuse of 1 is preferable but it doesn't really matter. You can label the height Y and the base X and one of the angles (not the 90 degrees) as theta. Then sin.theta and cos.theta will be X or Y depending on which angle you chose as theta. Then you Pythagoras Theorem which gives you the relationship X^2 + Y^2 = 1. Then sub in the X and Y which you found in terms of sin.theta and cos.theta.
You first have to draw a right-angle triangle. A hypotenuse of 1 is preferable but it doesn't really matter. You can label the height Y and the base X and one of the angles (not the 90 degrees) as theta. Then sin.theta and cos.theta will be X or Y depending on which angle you chose as theta. Then you Pythagoras Theorem which gives you the relationship X^2 + Y^2 = 1. Then sub in the X and Y which you found in terms of sin.theta and cos.theta.