142k views
1 vote
I(12π)= en ∫Cos³(2x)⋅[2+Sen(2x)]⁵dx

User Dmnc
by
7.7k points

1 Answer

4 votes

Final answer:

The solution to the integral is: (1/2)(2u + (1/4)Sin(4x))⋅[2+Sin(2x)]⁵ - (1/4)Cos(4x)⋅[2+Sin(2x)]⁶ - (1/6)⋅Cos(4x)⋅[2+Sin(2x)]⁶ + C.

Step-by-step explanation:

To solve the given integral ∫Cos³(2x)⋅[2+Sin(2x)]⁵dx, we can use the substitution method.

Here's how:

1. Let's make a substitution: u = Sin(2x). Taking the derivative of both sides with respect to x, we get du/dx = 2Cos(2x).

2. Rearranging the equation, we have dx = (1/2)du/Cos(2x).

3. Now, substitute u = Sin(2x) and dx = (1/2)du/Cos(2x) into the integral.

4. The integral becomes ∫(Cos³(2x)⋅[2+Sin(2x)]⁵)(1/2)du/Cos(2x).

5. Simplify by canceling out the Cos(2x) terms in the numerator and denominator: ∫(Cos²(2x)⋅[2+Sin(2x)]⁵)(1/2)du.

6. Next, simplify further: ∫(1/2)Cos²(2x)⋅[2+Sin(2x)]⁵du.

7. Expand the Cos²(2x) term using the identity Cos²(2x) = (1/2)(1 + Cos(4x)): ∫(1/2)(1 + Cos(4x))⋅[2+Sin(2x)]⁵du.

8. Distribute and simplify: ∫(1/2)(2 + Cos(4x) + 2⋅Cos(4x)⋅Sin(2x) + Cos(4x)⋅Sin²(2x))⋅[2+Sin(2x)]⁵du.

9. Now, integrate each term separately with respect to u:

  • - ∫(1/2)(2 + Cos(4x))⋅[2+Sin(2x)]⁵du = (1/2)(2u + (1/4)Sin(4x))⋅[2+Sin(2x)]⁵ + C₁
  • - ∫(1/2)(2⋅Cos(4x)⋅Sin(2x))⋅[2+Sin(2x)]⁵du = -(1/4)Cos(4x)⋅[2+Sin(2x)]⁶ + C₂
  • - ∫(1/2)(Cos(4x)⋅Sin²(2x))⋅[2+Sin(2x)]⁵du = -(1/6)⋅Cos(4x)⋅[2+Sin(2x)]⁶ + C₃

10. Finally, combining all the terms, the solution to the integral is:

(1/2)(2u + (1/4)Sin(4x))⋅[2+Sin(2x)]⁵ - (1/4)Cos(4x)⋅[2+Sin(2x)]⁶ - (1/6)⋅Cos(4x)⋅[2+Sin(2x)]⁶ + C,

where C = C₁ + C₂ + C₃ is the constant of integration.

Your question is incomplete, but most probably the full question was:

Solve the integral and explain .

I(12π)= ∫Cos³(2x)⋅[2+Sin(2x)]⁵dx

User Mr Bell
by
7.2k points