184k views
3 votes
Evaluate the following indefinite integral
∫(x²+1) ln(x³+3 x+1)/x³+3 x+1 d x

User Denza
by
8.1k points

1 Answer

5 votes

Final answer:

To evaluate the indefinite integral ∫(x²+1) ln(x³+3 x+1)/(x³+3 x+1) d x, we can use the method of integration by parts. First, we define u = ln(x³+3 x+1) and dv = (x²+1)/(x³+3 x+1) d x. After finding du and v, we apply the formula for integration by parts.

Step-by-step explanation:

To evaluate the indefinite integral ∫(x²+1) ln(x³+3 x+1)/(x³+3 x+1) d x, we can use the method of integration by parts. Let's define u = ln(x³+3 x+1) and dv = (x²+1)/(x³+3 x+1) d x.

Next, we need to find du and v:

  • du = (1/(x³+3 x+1)) * (3 x² + 3)
  • dv = (x²+1)/(x³+3 x+1) d x
  • v = ∫(x²+1)/(x³+3 x+1) d x

Now we can apply the formula for integration by parts:

∫u dv = uv - ∫v du

Plugging in the values, we have:

∫(x²+1) ln(x³+3 x+1)/(x³+3 x+1) d x = ln(x³+3 x+1) * ∫(x²+1)/(x³+3 x+1) d x - ∫[(3 x² + 3)/(x³+3 x+1)] ln(x³+3 x+1) d x

The second term on the right-hand side is a bit complex, but the first term is something we can evaluate:

∫(x²+1)/(x³+3 x+1) d x = ∫(1/x + 2/(x²(x+3))) d x = ln(x) + ln(x²+3)

So the final result is:

∫(x²+1) ln(x³+3 x+1)/(x³+3 x+1) d x = ln(x³+3 x+1) * [ln(x) + ln(x²+3)] - ∫[(3 x² + 3)/(x³+3 x+1)] ln(x³+3 x+1) d x

User Mnshahab
by
8.2k points