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Evaluate the integral ∫(6sin²(x)cos³(x))dx. (Use c for the constant of integration.)

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Final answer:

To evaluate the integral ∫(6sin²(x)cos³(x))dx, we can use the power-reduction formula for cosine and the substitution method to simplify and solve the integral. The final answer is (3/8)sin(2x) - (1/8)sin³(2x) + C.

Step-by-step explanation:

To evaluate the integral ∫(6sin²(x)cos³(x))dx, we can use the power-reduction formula for cosine: cos²(x) = (1 + cos(2x))/2. Applying this formula, we have:

∫(6sin²(x)cos³(x))dx = 6∫(sin²(x)(1 + cos(2x))/2*cos³(x))dx

Using the identity sin²(x) = (1 - cos(2x))/2, we can further simplify:

6∫(((1 - cos(2x))/2)(1 + cos(2x))/2*cos³(x))dx

Expanding and simplifying the integrand, we have:

6∫((1/4)(1 - cos²(2x))*cos³(x))dx

Now, we can use the substitution u = sin(2x), du = 2cos(2x)dx:

6(1/4)∫(1 - u²)du

Applying the power rule for integration, we get:

6(1/4)(u - u³/3) + C

Substituting u = sin(2x) back in, we have:

6(1/4)(sin(2x) - sin³(2x)/3) + C

Simplifying further:

(3/8)sin(2x) - (1/8)sin³(2x) + C

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