∫xx2+9 dx=\displaystyle\int x \sqrt{x^2 + 9}\,dx =∫xx2+9dx=A2(x2+9)3/23+C\dfrac{2(x^2+9)^{3/2}}{3} + C32(x2+9)3/2+CB(x2+9)3/22+C\dfrac{(x^2+9)^{3/2}}{2} + C2(x2+9)3/2+CC(x2+9)3/2+C(x^2+9)^{3/2} + C(x2+9)3/2+CD(x2+9)3/23+C\dfrac{(x^2+9)^{3/2}}{3} + C3(x2+9)3/2+Ccheck_circleExplanationu=x2+9u = x^2 + 9u=x2+9, du=2x dxdu = 2x\,dxdu=2xdx. ∫u du/2=u3/2/3\int \sqrt u\,du/2 = u^{3/2}/3∫udu/2=u3/2/3.