Learn how to solve problems step by step online. Find the integral int(5/(21-4x-x^2))dx. Rewrite the expression \frac{5}{21-4x-x^2} inside the integral in factored form. Simplify the division 5 by -1. The integral of a function times a constant (-5) is equal to the constant times the integral of the function. We can solve the integral \int\frac{1}{-25+\left(x+2\right)^2}dx by applying integration by substitution method (also called U-Substitution). First, we must identify a section within the integral with a new variable (let's call it u), which when substituted makes the integral easier. We see that x+2 it's a good candidate for substitution. Let's define a variable u and assign it to the choosen part.

Find the integral int(5/(21-4x-x^2))dx