Identify Problem: Identify the integral that needs to be solved.We need to find the integral of cos3(x) with respect to x.
Rewrite Integral: Rewrite the integral in a more convenient form.We can use the trigonometric identity cos2(x)=1−sin2(x) to rewrite cos3(x) as cos(x)⋅(1−sin2(x)).
Set Up Expression: Set up the integral with the rewritten expression.The integral becomes ∫cos(x)⋅(1−sin2(x))dx.
Use Substitution: Use substitution to solve the integral. Let u=sin(x), then du=cos(x)dx. The integral now becomes ∫(1−u2)du.
Integrate with u: Integrate with respect to u. The integral of 1 with respect to u is u, and the integral of u2 with respect to u is (u3)/3. So, ∫(1−u2)du=u−(u3)/3+C, where C is the constant of integration.
Substitute Back: Substitute back in terms of x. Since u=sin(x), we substitute back to get the integral in terms of x: sin(x)−(sin3(x))/3+C.