Math Problem Statement

Integrate

Integrate \( \int_1^3 (4x - 6x^2)(x^3 - x^2 + 8)^9 dx \)

Solution

The given integral appears to be:

13(4x6x2)(x3x2+8)9dx\int_1^3 (4x - 6x^2)(x^3 - x^2 + 8)^9 \, dx

Approach:

We'll use substitution to solve the integral. Let us break it down:

  1. Let u=x3x2+8u = x^3 - x^2 + 8.
  2. Then, dudx=3x22x\frac{du}{dx} = 3x^2 - 2x, which implies du=(3x22x)dxdu = (3x^2 - 2x)dx.

Now, rewrite 4x6x24x - 6x^2 in terms of 3x22x3x^2 - 2x: 4x6x2=2(3x22x).4x - 6x^2 = -2(3x^2 - 2x).

Thus, the integral becomes: 13(4x6x2)(x3x2+8)9dx=2u9du.\int_1^3 (4x - 6x^2)(x^3 - x^2 + 8)^9 dx = -2 \int u^9 \, du.

Compute the integral:

The integral of u9u^9 is: u9du=u1010.\int u^9 \, du = \frac{u^{10}}{10}.

Substitute this back: 2u9du=2u1010=u105.-2 \int u^9 \, du = -2 \cdot \frac{u^{10}}{10} = -\frac{u^{10}}{5}.

Back-substitute u=x3x2+8u = x^3 - x^2 + 8:

u105=(x3x2+8)105.-\frac{u^{10}}{5} = -\frac{(x^3 - x^2 + 8)^{10}}{5}.

Apply the limits x=1x = 1 to x=3x = 3:

Now evaluate: 13(4x6x2)(x3x2+8)9dx=(x3x2+8)10513.\int_1^3 (4x - 6x^2)(x^3 - x^2 + 8)^9 dx = -\frac{(x^3 - x^2 + 8)^{10}}{5} \bigg|_1^3.

  1. When x=3x = 3: u=3332+8=279+8=26.u = 3^3 - 3^2 + 8 = 27 - 9 + 8 = 26.

  2. When x=1x = 1: u=1312+8=11+8=8.u = 1^3 - 1^2 + 8 = 1 - 1 + 8 = 8.

Thus: 13(4x6x2)(x3x2+8)9dx=26105+8105.\int_1^3 (4x - 6x^2)(x^3 - x^2 + 8)^9 dx = -\frac{26^{10}}{5} + \frac{8^{10}}{5}.

Final Answer:

26105+8105\boxed{-\frac{26^{10}}{5} + \frac{8^{10}}{5}}

Would you like me to simplify further, expand the steps, or compute the numerical value?


5 Related Questions:

  1. What are the steps to determine a substitution variable in integrals?
  2. How can substitution be applied when there are powers of a binomial function?
  3. Why is substitution effective in simplifying integrals with powers of a polynomial?
  4. How do definite integrals differ from indefinite integrals in computation?
  5. What are the best ways to verify substitution-based integration?

Tip:

Always check if the derivative of the substitution matches the differential in the integral for a seamless transformation.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Definite Integration
Substitution Method
Polynomial Functions
Exponents and Powers

Formulas

\( \int u^n du = \frac{u^{n+1}}{n+1} + C \)
\( u = x^3 - x^2 + 8 \), \( du = (3x^2 - 2x) dx \)

Theorems

Fundamental Theorem of Calculus

Suitable Grade Level

Grades 11-12 (Advanced High School Calculus)