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# Converting between trigonometric ratios example: write all ratios in terms of sine

Let's see how we can write all the other trigonometric ratios in terms of Sine using trigonometric identities. Created by Aanand Srinivas.

## Want to join the conversation?

• If cosA= √1-sin^2A
Can we say that
cosA = sinA √1
• Well, the square root of 1 is just 1, so essentially, what you are saying is that cosA = sinA.
We know, from the basic definitions of sine and cosine, that sin is opposite/hypotenuse, and cos is adjacent/hypotenuse.
So no, what you stated is wrong.
Second, I am not really sure how you arrived at that conclusion, but from what I infer, you assumed that the square root was separate for the one and the sinA. (Even so, you would still get 1-sinA)
Hope this helped!