sinx+sin2x+sin3x的最大值

sinx*sin2x*sin3x=? sin3x-sin2x+sinx=0 sin3x+cosx-cos3x-sinx/2(sin2x+cos2x) sinx+sin2x+sin3x+.+sinnx=?求和. 求证sinx+sin3x+sin2x=1+cos2x+cosx 解三角方程式sinx+sin2x=sin3x,0 1+sinX+sin2X+sin3X=cosX-cos2X+cos3X 求数学积分∫（sinx*sin2x*sin3x）dx 求函数f(x)=sin2x+sinx+cosx的最大值 求出下列函数的周期1.y=cos(X/4)+3sin(X/3)2.y=sinX+1/2(sin2X)+1/3(sin3X 谁能帮忙计算一下sinx+sin2x+sin3x+~+sinnx之和,要关键步骤. limx→0（6x-sinx-sin2x-sin3x）/x^3求极限