Math Problem Statement

∫ (1 / (2x + 1)) dx

Solution

The problem asks to compute the integral:

12x+1dx\int \frac{1}{2x + 1} \, dx

To solve this, we can use the method of substitution.

Let: u=2x+1u = 2x + 1 Then, differentiate both sides with respect to xx: du=2dxdx=du2du = 2 \, dx \quad \Rightarrow \quad dx = \frac{du}{2}

Now, substitute these into the integral:

12x+1dx=1udu2=121udu\int \frac{1}{2x + 1} \, dx = \int \frac{1}{u} \cdot \frac{du}{2} = \frac{1}{2} \int \frac{1}{u} \, du

The integral of 1u\frac{1}{u} is lnu\ln |u|, so we have:

12lnu+C\frac{1}{2} \ln |u| + C

Finally, substitute u=2x+1u = 2x + 1 back into the result:

12ln2x+1+C\frac{1}{2} \ln |2x + 1| + C

Thus, the solution is:

12x+1dx=12ln2x+1+C\int \frac{1}{2x + 1} \, dx = \frac{1}{2} \ln |2x + 1| + C

Would you like more details on any step?

Here are 5 related questions for further exploration:

  1. How does substitution help simplify integrals like this?
  2. What is the integral of 1ax+b\frac{1}{ax + b} in general?
  3. How do we apply logarithmic properties to integrals involving lnu\ln |u|?
  4. Can this integral be solved using partial fractions or other methods?
  5. What happens if the denominator is a quadratic expression instead of linear?

Tip: Always check if substitution is a suitable method for simplifying an integral. It can be very helpful for linear expressions in the denominator.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Integral Calculus
Substitution Method
Logarithmic Integration

Formulas

∫ (1 / (ax + b)) dx = (1 / a) ln |ax + b| + C

Theorems

Substitution Method in Integration
Logarithmic Integration Theorem

Suitable Grade Level

Grades 11-12 (Advanced Calculus)