Prove it please
answer only if you know​

Part (c)

We'll use this identity

to say

Similarly,

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The key takeaways here are that

Therefore,

The identity is confirmed.

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Part (d)

Similarly,

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We'll square each equation

and

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Let's compare the results we got.

Now if we add the terms straight down, we end up with on the left side

As for the right side, the sin(A)cos(A) terms cancel out since they add to 0.

Also note how and similarly for the sin^2 terms as well.

The right hand side becomes but that's always equal to 1 (pythagorean trig identity)

This confirms that is an identity

this is not the answer this is just a question. is this middle school math?

step-by-step explanation: