∫xcosx+dx等于多少

乐义黛2107∫cos(x+2)dx的值是多少 -
汤杜谭19757701575 ______[答案] 解 ∫cos(x+2)dx =∫cos(x+2)d(x+2) =∫cosudu =sinu+C =sin(x+2)+C(如果对你有帮助,请设置“好评”,谢谢!)

乐义黛2107求x(cosx)方dx的积分 -
汤杜谭19757701575 ______[答案] ∫xcos^2 x dx =∫x(cos2x+1)/2 dx =1/2*∫xcos2xdx+1/2*∫xdx =1/4∫xcos2xd2x+1/4∫dx^2 =1/4∫xdsin2x +x^2/4 =1/4 *xsin2x-1/4∫sin2xdx +x^2/4 =xsin2x/4+x^2/4-1/8∫sin2xd2x =xsin2x/4+x^2/4+1/8∫dcos2x =xsin2x/4+x^2/4+cos2x/8 + C

乐义黛2107∫(cosx+1)dx等于? -
汤杜谭19757701575 ______ ∫(cosx+1)dx=∫cosxdx+∫1dx=sinx+x+c

乐义黛2107不定积分 ∫xsinx dx 等于多少? -
汤杜谭19757701575 ______[答案] ∫xsinxdx=-∫x dcosx =-x cosx +∫cosx dx= sinx -x cosx ∫xe^x dx= ∫x de^x =x e^x-∫e^x dx =(x-1)e^x 就是分部积分法的应用

乐义黛2107若f(x)连续 ∫f(t)dt在0到x的积分是x^2/2 则∫1/√x * f(√x)dx 在0到4上得积分等于多少 -
汤杜谭19757701575 ______[答案] ∫[0,4] 1/√x * f(√x)dx =2∫[0,4] f(√x)d√x =2*x/2[0,4] =4

乐义黛2107∫1/(cosx+sin2x)dx 等于多少, -
汤杜谭19757701575 ______[答案] ∫1/(cosx+sin2x)dx = ∫1/(cosx+2sinx*cosx)dx = ∫1/ cosx*(1+2sinx)dx 分子分母同时乘以cosx =∫ cosx / [cos²x*(1+2sinx)] dx = ∫ 1/ [(1-sin²x)*(1+2sinx)] d(sinx) =1/3 * ∫ (2sinx-1) /(1-sin²x) + 4/(1+2sinx) d(sinx) =1/3 * ∫ [ 0.5/(1-sinx) - 1.5/(1+sinx) + 4/(1+2...

乐义黛2107∫( - a到a)(xcosx - 5sinx+2)dx= -
汤杜谭19757701575 ______[答案] ∫(xcosx-5sinx+2)dx=∫xcosxdx-5∫sinxdx+2x+C=∫xd(sinx)+5cosx+2x+C=x*sinx-∫sinxdx+5cosx+2x+C=xsinx+cosx+5cosx+2x+C=xsinx+6cosx+2x+C代入上下限得,∫(xcosx-5sinx+2)dx=4a

乐义黛2107不定积分∫cos2(x+π/3) dx等于多少? -
汤杜谭19757701575 ______[答案] ∫cos2(x+π/3) dx =1/2 ∫cos2(x+π/3)d2(x+π/3) =1/2sin2(X+π/3)+C

乐义黛2107若∫xf(x)dx=lnx+c,则∫f(x)dx等于多少? -
汤杜谭19757701575 ______[答案] ∫xf(x)dx=lnx+c xf(x) = 1/x f(x) = 1/x^2 ∫f(x)dx = -1/x + C

乐义黛2107∫sin(x+π/3)dx等于多少,上限为π,下限为π/3,求详的细解题步骤,O(∩ - ∩)O谢谢! -
汤杜谭19757701575 ______[答案] ∫(π/3,π) sin(x+π/3)dx =∫(π/3,π) sin(x+π/3)d(x+π/3) = -cos(x+π/3)|(2π/3,4π/3) = -cos5π/3+cosπ =-3/2