∫(1,1/2) dx∫(2,1/2) 1/2 dy=?怎么求最好有过程哈

∫dx/(1+2cosx) ∫dx/(1+sinxcosx)^2 ∫(x-1)^2dx, ∫x^1/2dx ∫[dx/(e^x(1+e^2x)]dx 计算积分 ∫[sinx+(x^2)]dx ∫xe^[(-x^2)]dx ∫{1/[根号（x+1)]}dx∫[sinx+(x^2)]dx∫xe^[(-x^2)]dx∫{1/[根号（x+1)]}dx ∫x-根号下x dx ∫lx-2l dx ∫1/根号下（4-x^2) dx ∫e^(-x) dx ∫2/根号下x dx ∫(1/x^2)sin(1/x) dx [1/（2+sinx)]dx ∫1/(x^2+1)^2dx ∫dx/(1+√(1-x^2)) 微积分∫1/(1+x^2)dx ∫1/(1+cos^2(x)) dx ∫1/(1+2根号x)dx ∫1/x^2+x+1dx ∫1/(x^2+x+1)dx ∫dx/[√(2x-1)+1] ∫1/(1+e^x)^2dx ∫1/1-x^2dx=