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Prove the trigonometric equation: (cos x)(tanx + sinx cotx) = sinx + cos^2x.

User Heisen
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Final answer:

By substituting tan x with sin x/cos x and cot x with cos x/sin x, we simplify (cos x)(tan x + sin x cot x) to sin x + cos x, proving the equation.

Step-by-step explanation:

To prove the trigonometric equation (cos x)(tanx + sinx cotx) = sinx + cos2x, we must manipulate the left-hand side to show that it is equal to the right-hand side. Begin by recalling that tan x is equal to sin x/cos x and cot x is equal to cos x/sin x. This lets us rewrite the left-hand side as follows:

cos x(tan x + sin x cot x) = cos x(sin x/cos x + sin x(cos x/sin x))

Simplify by canceling common terms:

cos x(sin x/cos x + sin x(cos x/sin x)) = cos x(sin x/cos x + 1)

This further reduces to:

sin x + cos x

Which is the right-hand side of the equation we are trying to prove. Therefore, the given trigonometric equation is proved to be true.

User JastinBall
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