求和S=sin^2 1度+sin^2 2度+sin^2 3度+...+sin^2 88度+sin^2 89度

求和S=sin^2 1度+sin^2 2度+sin^2 3度+...+sin^2 88度+sin^2 89度 sin^2 (0°)+sin^2( 1°)+.+sin^2(90du) 求和 sin a+sin 2a +sin 3a +...+sin na怎么求和? sin a+sin 2a +sin 3a +...+sin na怎么求和? 数列求和 sin²1°+sin²2°+sin²3°+.+sin²88°+sin²89°数列求和 sin²1°+sin²2°+sin²3°+.+sin²88°+sin²89° 求详细解答过程! s = 2*sin(x)-sin(2*x)+2/3*sin(3*x)-1/2*sin(4*x)+2/5*sin(5*x)用matlab画图,求教啊 为什么sin-sin^2=1/4 S=(cos^2 x+cos^4 x+.+cos^2n x)+(sin^2x+sin^4 x+.+sin^2n x)数列求和题!答案是(cos^4 x+sin^4 x-cos^2n+4 x-sin^2n+4 x)/sin^2 x.cos^2 x 求证:sin^2/(sin-cos) - (sin+cos)/(tan^2 -1) =sin+cos sin²0+sin²1+sin²2+……+sin²180= S(1-sin^2x)d(sinx)为什么=sinx-1/3sin^3x? 傅里叶级数作图f（x）=2sin[x] - sin[2x] + 2/3sin[3x] - 1/2sin[4x]我用mathematica输入程序Plot[{2sin[x],-2sin[x],2sin[x] - sin[2x],-2sin[x] + sin[2x],2sin[x] - sin[2x] + 2/3sin[3x],-2sin[x] + sin[2x] - 2/3sin[3x],2sin[x] - sin[2x] + 2/3si 【证明】Sin A+sin B=2Sin 22 在△ABC中,求证；sin^(A/2)+sin^(B/2)+sin^(C/2)=1-2sin(A/2)sin(B/2)sin(C/2） 懂得进.证明,sina+sin(a+b)+sin(a+2b)+...sin(a+nb)=sin(a+ab/2)sin[(n+1)b/2]/sin(b/2) sin²1°+sin²2°+sin²3°+……+sin²87°+sin²88°+sin²89°= sin²1°+sin²2°+sin²3°+...+sin²88°+sin²89°+sin²90°=等于多少? sin(arccos(2sin(a)))=