Rewrite Trig Functions: Rewrite the integral in terms of sine and cosine to make it easier to integrate.The integral is already in terms of sine and cosine, so no rewriting is necessary.
Use Trig Identity: Recognize that sin2(x)=1−cos2(x) and rewrite the integral using this identity.∫cos2(x)sin3(x)dx=∫cos2(x)sin(x)⋅(1−cos2(x))dx
Expand Integrand: Expand the integrand to separate the terms.∫cos2(x)sin(x)⋅(1−cos2(x))dx=∫cos2(x)sin(x)dx - ∫cos2(x)sin(x)⋅cos2(x)dx
Simplify Integral: Simplify the integral. ∫(cos2(x)sin(x)dx)−∫(sin(x)⋅cos2(x)cos2(x)dx)=∫(cos2(x)sin(x)dx)−∫(sin(x)dx)
Recognize Integrals: Recognize that the first integral is the integral of tan(x)⋅sec(x) and the second integral is the integral of sin(x).∫(cos2(x)sin(x)dx)−∫(sin(x)dx)=∫(tan(x)⋅sec(x)dx)−∫(sin(x)dx)
Integrate Separately: Integrate tan(x)⋅sec(x) and sin(x) separately.The integral of tan(x)⋅sec(x) is sec(x), and the integral of sin(x) is −cos(x).∫(tan(x)⋅sec(x)dx)−∫(sin(x)dx)=sec(x)−(−cos(x))+C
Combine Results: Combine the results to get the final answer. sec(x)−(−cos(x))+C=sec(x)+cos(x)+C
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