Using the fundemental identities and the Pythagorean Identities, I go over multiple examples of verifying trigonometric identities.
It is very important in proofs that you do not handle it like an equation moving terms and factors from side to side.
NOTE from: Rick A
We should use the 'triple hyphen' to indicate an identity instead of an equation so students don't think your solving an equation. I get this notion from recalling the textbooks from my high-school days.
I was corrected that what I am trying to prove should not be within the body of the proof. This implies it has already been assumed to be true. So proofs should be shown like this example:
cos^2(x)(tan^2(x)+1)=1
Proof:
cos^2(x)(tan^2(x)+1)=cos^2(x)*sec^2(x)
=cos^2(x)(1/cos^2(x))
=1
Verifying Trigonometric Identities Part 2
https://www.youtube.com/watch?v=q8k-sS7qRts
Verifying Trigonometric Identities Part 3
https://www.youtube.com/watch?v=mAnw4ImaPK0
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