解:V=πr^2h=π*4x^2*(x+2)=4π(x^3+2x^2)当x=3时V=4π(3^3+2*3^2)=180π
V=2X^2*(X+2)*π当X=32X=6X+2=56^2*3.14*5=565.2^3
180派
V=180π