∫sin+5xdx
穆空殃4610sin2cos3xdx求不定积分 -
宣珊钓18133214081 ______[答案] cos3x= ∫sin2xcos3xdx =∫1/2(sin(2x+3x)+sin(2x-3x))dx =1/2∫sin5xdx-1/2∫sinxdx =1/10∫sin5xd5x+1/2∫dcosx =(cosx)/2-(cos5x)/10+C
穆空殃4610求∫sin5xsin7xdx详细解答过程谢谢
宣珊钓18133214081 ______ sin5xsin7x=(1/2)[cos2x-cos12x]; ∫sin5xsin7xdx =(1/4)sin2x-(1/24)sin12x+C
穆空殃4610求一道不定积分~求这道不定积分:sin2xcos3xdx -
宣珊钓18133214081 ______[答案] 首先你要知道这条积化和差公式: sinAcosB=(1/2)[sin(A+B)+sin(A-B)] 证明的话直接就将等式右边展开就行.这里先略过,进入主题. ∫sin2xcos3xdx =(1/2)∫[sin5x+sin(-x)]dx =(1/2)∫sin5xdx-(1/2)∫sinxdx (前者用凑微分法) =(1/10)∫sin5xd(5x)+...
穆空殃4610化简 三角函数one:∫sin2xcos3xdx怎么得这步 =∫1/2(sin5x - sinx)dxtwo:∫sin5xsin7xdx=∫1/2(cos2x - cos12x)dx -
宣珊钓18133214081 ______[答案] 他们用的都是积化和差 公式是:1.sinXcosY=0.5*[sin(X+Y)+sin(X-Y)] 2.sinXsinY=-0.5[cos(X+Y)-cos(X-Y)] 带进去,再利用诱导公式就得到下面的式子了……
穆空殃4610求∫sin3xsin5xdx的值? -
宣珊钓18133214081 ______[答案] ∫sin3xsin5xdx =-(1/2)∫(cos8x-cos2x)dx =-(1/2)((1/8)sin8x-(1/2)sin2x)+C =(-1/16)sin8x+(1/4)sin2x+C
穆空殃4610大一高数~求不定积分∫sin3xsin5xdx -
宣珊钓18133214081 ______[答案] 须知公式:sinAsinB = (1/2)[cos(A-B)-cos(A+B]∫sin(3x)sin(5x) dx= (1/2)∫[cos(-2x)-cos(8x)] dx= (1/2)∫cos2x dx - (1/2)∫cos8x dx= (1/4)∫cos2x d(2x) - (1/16)∫cos8x d(8x)= (1/4)sin2x - (1/16)sin8x + C
穆空殃4610∫sin 8x cos 5xdx一个是8X一个是5X怎么办... -
宣珊钓18133214081 ______[答案] sinα·cosβ=(1/2)[sin(α+β)+sin(α-β)] ∫sin 8x cos 5xdx=0.5∫sin13xdx+0.5∫sin3xdx= -1/26cos13x-1/6cos3x+C
穆空殃4610x^6*sinx的不定积分怎么求? -
宣珊钓18133214081 ______[答案] ∫x^6sinxdx =-∫x^6dcosx = - x^6cosx +6∫x^5cosxdx =- x^6cosx +6∫x^5dsinx =- x^6cosx +6x^5sinx -30∫x^4sinxdx =- x^6cosx +6x^5sinx +30∫x^4dcosx = - x^6cosx +6x^5sinx +30x^4cosx -120∫x^3cosxdx =- x^6cosx +6x^5sinx +30x^4cosx -120∫x^3dsinx =- ...
穆空殃4610∫( - a到a)(xcosx - 5sinx+2)dx= -
宣珊钓18133214081 ______[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
穆空殃4610求一个定积分定积分:下限(π/6+α),上限(5π/6+α),(3/2π)∫[π/6+α,5π/6+α]USinxdx的定积分怎么算?(有步骤的) -
宣珊钓18133214081 ______[答案] 那个U又是什么呢?sinx的原函数就是-cosx+C.所以∫[π/6+α,5π/6+α]Sinxdx=cos(π/6+α)-cos(5π/6+α)=根号3cosa.最后结果再乘以3/2π=9cosa/2π