# Math Help - Evaluate the Integral

1. ## Evaluate the Integral

$\int_0^3{\,3dx/(x+1)}$

How can I find the antiderivative of 3dx/(x+1)?

2. Let $*u = (x+1) \implies du = dx \implies [0,3] \implies [1,4]$*
$

3\int_1^4{\frac{du}{u}} = 3ln(4)-3ln(1) = 3ln(4) = ln(64)
$

3. I know how to evaluate the integral, I just want to know how to get the antiderivative of 3dx/(x+1)...

4. Originally Posted by katchat64
I know how to evaluate the integral, I just want to know how to get the antiderivative of 3dx/(x+1)...
U know that the derivative of $\ln x=\frac{1}{x}$ so in this case the antiderivative of $\frac{3}{x+1}$ is $3\ln(x+1)$

5. Thank you, that's more of an elaborate explanation.