we have to know that to find concavity we need the second derivative and since we are looking for concave up, it's where y'' > 0. Given that y is an integral, y' is the integral evaluated at x, so it's y' = 6/(1+2x+ x^2), then for the second derivative I used the quotient rule. I set the second derivative > 0 and see that x > -1 gives us concave up