how to show the sin^2 x +cos ^2 x =1

Question

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plz i want to show the sin^2 x +cos ^ x =1

Sasini Jan 20, 2015

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Best Answer

Notice that if we have a unit circle, any point on that circle can be represened as (rcosx, rsinx)

And using the Pythagorean Theorem, (rcosx)^2 + (rsinx)^2 = 1

But, since this is a unit circle, r = 1 ..... so

cos^2(x) + sin^(2)x = 1

CPhill Jan 20, 2015

CPhill · Answer 1 · 2015-01-20T04:35:11

Notice that if we have a unit circle, any point on that circle can be represened as (rcosx, rsinx)

And using the Pythagorean Theorem, (rcosx)^2 + (rsinx)^2 = 1

But, since this is a unit circle, r = 1 ..... so

cos^2(x) + sin^(2)x = 1

Guest · Answer 2 · 2015-01-20T03:27:30

10 es el answer