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**Kiran****Member**- Registered: 2006-11-15
- Posts: 177

given that 0 degrees <_ x < 360 degrees , solve the following equation :

cos x - sqrt(1 - cos^2 x) = 0

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

A basic identity is that sin² x + cos² x = 1.

Therefore, 1 - cos² x = sin² x, and so sqrt(1 - cos² x) = sin x.

So now you have cos x - sin x = 0. And it should be easy after that.

Why did the vector cross the road?

It wanted to be normal.

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