微积分x+1/[x*√(x-2)]dx

2个回答

  • 答:

    设t=√(x-2)>0,x=t^2+2,dx=2tdt

    原式

    =∫{x+1/[x√(x-2)]}dx

    =∫{t^2+2+1/[(t^2+2)t]} 2tdt

    =∫(2t^3+4t)dt+2∫ 1/(t^2+2)dt

    =(1/2)t^4+2t^2+(2/√2)arctan(t/√2)+C1

    =(1/2)(x-2)^2+2(x-2)+√2arctan[√(x-2)/√2]+C2

    =(1/2)(x-2)^2+2x+√2arctan√(x/2-1)+C3

    =(x^2)/2+√2arctan√(x/2-1)+C