Sin Cos Integral 3B7493
1. We are asked to evaluate the integral $$\int \sin^2 x \cos^3 x \, dx$$.
2. To solve this integral, we use trigonometric identities and substitution. Important rules:
- Express powers of sine or cosine in terms of the other function if possible.
- Use substitution when the derivative of one function appears in the integral.
3. Rewrite $$\cos^3 x = \cos^2 x \cdot \cos x = (1 - \sin^2 x) \cos x$$ using the Pythagorean identity $$\cos^2 x = 1 - \sin^2 x$$.
4. Substitute into the integral:
$$\int \sin^2 x \cos^3 x \, dx = \int \sin^2 x (1 - \sin^2 x) \cos x \, dx$$.
5. Let $$u = \sin x$$, then $$du = \cos x \, dx$$.
6. The integral becomes:
$$\int u^2 (1 - u^2) \, du = \int (u^2 - u^4) \, du$$.
7. Integrate term-by-term:
$$\int u^2 \, du - \int u^4 \, du = \frac{u^3}{3} - \frac{u^5}{5} + C$$.
8. Substitute back $$u = \sin x$$:
$$\frac{\sin^3 x}{3} - \frac{\sin^5 x}{5} + C$$.
Final answer:
$$\int \sin^2 x \cos^3 x \, dx = \frac{\sin^3 x}{3} - \frac{\sin^5 x}{5} + C$$.