三道有关定积分题,人教版,55页的要详解··········计算定积分1.∫[2,1] (x^2-2x-3/x) dx2.∫[2,1] (e^2-2/x) dx3.∫[π/2,0] (3x+sinx) dx在线等·······拜托啦············

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三道有关定积分题,人教版,55页的要详解··········计算定积分1.∫[2,1] (x^2-2x-3/x) dx2.∫[2,1] (e^2-2/x) dx3.∫[π/2,0] (3x+sinx) dx在线等·······拜托啦············
三道有关定积分题,人教版,55页的要详解··········
计算定积分
1.∫[2,1] (x^2-2x-3/x) dx
2.∫[2,1] (e^2-2/x) dx
3.∫[π/2,0] (3x+sinx) dx
在线等·······拜托啦············

三道有关定积分题,人教版,55页的要详解··········计算定积分1.∫[2,1] (x^2-2x-3/x) dx2.∫[2,1] (e^2-2/x) dx3.∫[π/2,0] (3x+sinx) dx在线等·······拜托啦············
1.∫[2,1] (x^2-2x-3/x) dx=∫[2,1] x^2dx-∫[2,1] 2xdx-∫[2,1]3/xdx
=1/3x^3[2,1]-x^2[2,1]-3lnx[2,1]
=7/3-3-3ln2=-2/3-3ln2
2.∫[2,1] (e^2-2/x) dx=.∫[2,1] e^2dx-.∫[2,1] 2/xdx
=e^2x[2,1]-2lnx[2,1]
=e^2-2ln2
3.∫[π/2,0] (3x+sinx) dx
=.∫[π/2,0]3xdx+.∫[π/2,0]sinxdx
=3/2x^2[π/2,0]-cosx[π/2,0]
=3/8π^2+1