Hello, Bashyboy!

I am given a righ-triangle, where: h = sqrt(17), a = 1, and b = 4.

I am suppose to find the exact value of the trigonometric sin 4x.

So, I use the double angle formula, and what results is 2 sin 2x cos 2x.

Then, I use the the double angle formulas again,

. . and get: 2(2 sin x cos x)(1 - sin^2 x) .Here!

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