sin3x

lim(x+sin3x)/(x-sin3x)的极限此题楼主应该打少了x→0或x→∞的条件,不过无论是上述哪种情况,均可利用多次洛必达法则进而求得答案【分子分母分别求导】原式=lim(1+3cos3x)/(1-3cos3x)=lim(-9si

sin3x+|sin3x|的最小正周期?等于sin3x的周期,因|sin3x|快一倍.=2Pi/3

sinx+sin2x+sin3x求最值方法一:sinx+sin2x+sin3x=sinx+2sinx.cosx+sin2x.cosx+cos2x.sinx=sinx+2sinx.cosx+2sinx.cosx.cosx+sinx(cosx.

sinx*sin2x*sin3x=?如果是相乘的话,那么就是：sinx*sin2x*sin3x=sinX*2sinX*cosX*sin(2X+X)=2sinX*sinX*cosX*(sin2X*cosX+cos2X*sinX)=2sinX*

sin3x/sinx+cos3x/cosxsin(3x)/sinx+cos(3x)/cosx=[sin(3x)cosx+cos(3x)sinx]/(sinxcosx)=sin(3x+x)/[(1/2)sin(2x)]=2sin(4x)/si

sin3x用换元法计算不定积分

sin3x、cos3x等于好多?sin3a=3sina-4sin³acos3a=4cos³a-3cosa推导方法如下：sin3a=sin(2a+a)=sin2a×cosa+cos2a×sina=2×sina×cosa×c

y=sin3x+cos3x 

sin3x＋cos3x等于sin3x+cos3x=√2(√2/2*sin3x+√2/2cos3x)=√2(sin3xcosπ/4+cos3xsinπ/4)=√2sin(3x+π/4)

cos3xsin3x移动cos3x怎么移动得到sin3x?向右平移π/6个单位成为：sin(3x-π/2）向右平移派/6个单位cos3x让(-3x+2kπ+π/2)，3x先去相反数在平移2kπ+π/2=sin3x（利用正弦和余弦的关系得到）

Limsin3x------------=多少?x-0x+tan7xLimsin3x----------------x-0x+tan7xLim3x----------------x-0x+tan7xLim3=----------------

求y=sin3x•sin3x的周期

sinx+sin5x+sin3x=0sin(3x-2x)+sin(3x+2x)+sin3x→sin3xcos2x-cos3xsin2x+sin3xcos2x+cos3xsin2x+sin3x→sin3xcos2x+sin3xcos2x+si

sin3x-sin2x+sinx=0sin3x=sin(2x+x)=sin2xcosx+cos2xsinx=2sinxcosxcosx+cos2xsinx=2sinxcos²x+cos2xsinxsin3x-sin2x+sinx=

sinx+sin2x+sin3x的最大值没法用笔算的,数值解约为2.4996076043200564sin3x=sin(x+2x)=sinxcos2x+cosxsin2xsin2x=2sinxcosxcos2x=1-2sin^2x最后化成只

y=sin3x的导数y'=3cos3x3cos3x

(sin3x+sinx)/(cos3x+cosx)=sinα+sinβ=2sin[(α+β)/2]cos[(α-β)/2]cosα+cosβ=2cos[(α+β)/2]cos[(α-β)/2]所以：(sin3x+sinx)/(cos3x+c

y=sin3x的导数y=sin3xy'=3cos3x

sin3x/sinx-cos3x/cosx化简原式=(sin3x*cosx-cos3x*sinx)/(sinx*cosx)=2sin(3x-x)/sin2x=2sin3x/sinx-cos3x/cosx=-(cos3x/cosx-sin3x

lim(tan5x-cosx+1)/sin3xlim（x-->0)(tan5x-cosx+1)/sin3x=lim（x-->0)(5x-1+1)/3x=5/3