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问题: 求定积分

请过程

解答:

1
∫<0,π/2>e^sinx*cosxdx
=∫<0,π/2>e^sinxd(sinx)
=[e^sinx]|<0,π/2>
=e^sin(π/2)-e^sin0
=e-1

2
∫<0,π/2>xcosxdx
=∫<0,π/2>xd(sinx)
=[x*sinx]|<0,π/2>-∫<0,π/2>sinxdx
=[(π/2)*sin(π/2)-0*sin0]+[cosx]|<0,π/2>
=(π/2)+[cos(π/2)-cos0]
=(π/2)+0-1
=(π/2)-1

3
∫<0,1>x*e^(x^2/2)dx
=∫<0,1>e^(x^2/2)d(x^2/2)
=[e^(x^2/2)]|<0,1>
=e^(1/2)-e^0
=√e-1