sin3xcos2x

萧良顷4581sin3xsinx)为什么等于1/2(cos2x - cos4x)? -
陆艳单15888401575 ______[答案] sin3xsinx =sin(x+2x)sinx =(sinxcos2x+cosxsin2x)sinx =sin²xcos2x+sinxcosxsin2x =(1/2)(1-cos2x)cos2x+(1/2)sin²2x =(1/2)cos2x-(1/2)cos²2x+(1/4)(1-cos4x) =(1/2)cos2x-(1/4)(1+cos4x)+1/4-(1/4)cos4x =(1/2)cos2x-1/4-(1/4)cos4x+1/4-(1/4)cos4x =(1/2...

萧良顷4581求积分sin3xcos2xdx -
陆艳单15888401575 ______[答案] 用积化和差公式简化即可: 原式=1/2∫(sin5x+sinx)dx =-1/2(1/5 cos5x+cosx)+C

萧良顷4581sin3xcos2xdx的不定积分为多少 -
陆艳单15888401575 ______[答案] 先做积化和差: 2sin3x*cos2x=sin5x+sinx 下面就简单了,直接化为正弦函数的积分

萧良顷4581高阶导数怎么计算 5.(3) -
陆艳单15888401575 ______ 5、(3)一阶导数为6(x+10)^5,二阶为6*5(x+10)^4,依次类推:五阶为6!(x+10),所以f^5(0)=10*6!=7200 六阶为6!=720

萧良顷4581cos3xcos2x求积分的详解 -
陆艳单15888401575 ______ cos3xcos2x=1/2[cos5x+cosx] 所以, ∫cos3xcos2xdx=1/2*∫(cos5x+cosx)dx =1/10*sin5x+1/2*sinx+C C表示任意常数

萧良顷4581求y=cos3xcos2x的原函数 -
陆艳单15888401575 ______ cos5x=cos(3x+2x)=cos3xcos2x-sin3xsin2x cosx=cos(3x-2x)=cos3xcos2x+sin3xsin2x cosx+cos5x=2cos3xcos2x cos3xcos2x=1/2(cosx+cos5x) ∫cos3xcos2xdx =∫1/2(cosx+cos5x)dx =1/2∫cosxdx+1/2∫cos5xdx =1/2∫cosxdx+1/10∫cos5xd5x =1/2sinx+1/10sin5x+C

萧良顷4581cos3xcos2x求积分的详解 -
陆艳单15888401575 ______[答案] cos3xcos2x=1/2[cos5x+cosx] 所以, ∫cos3xcos2xdx=1/2*∫(cos5x+cosx)dx =1/10*sin5x+1/2*sinx+C C表示任意常数

萧良顷4581(sin4X+sinX)/sin4X=sin3X/sin2x化成sin4X+sinX=2sin3xcos2x -
陆艳单15888401575 ______ sin4x=2sin2xcos2x (sin4X+sinX)/sin4X=(sin4X+sinX)/(2sin2xcos2x)=sin3X/sin2x 所以sin4X+sinX=(sin3X/sin2x)*(2sin2xcos2x)=2sin3xcos2x 望采纳,谢谢

萧良顷4581求y=sin3x*sin2x的n阶导数 -
陆艳单15888401575 ______[答案] y(1)=6cos3xcos2x y(2)=6^2*sin3xsin2x ∴n是奇数时,y(n)=6^n*cos3xcos2x; n是偶数时,f(n)=6^n*sin3xcos2x

萧良顷4581若cos2xcos3x=sin2xsin3x,则x的一个值是( )a 36° b 45°c 18度d 30° -
陆艳单15888401575 ______[答案] cos3xcos2x-sin3xsin2x=0 cos(3x+2x)=0 cos5x=0 所以x=18时,cos5x=cos90=0 选C