sin(pi)

sin(pi/12)=?cos(π/6)=1-2[sin(π/12)]^2所以sin(π/12)=√[(1-cos(π/6)/2]=√[(3-√3)/6]sin(pi/12)=sin(pi/3-pi/4)=sinpi/3cospi/4-co

求级数sin(pi/6)+sin(2pi/6)+sin(3pi/6)+.+sin(npi/6)+.的部分和.（pi为圆周率）一个周期之内：sin(π/6)=1/2sin(2π/6)=(根号3)/2sin(3π/6)=1sin(4π/6)=(

化简：sin(2pi-a)sin(pi+a)cos(-pi-a)/sin(3pi-a)cos(pi-a)化简：sin(2pi-a)sin(pi+a)cos(-pi-a)---------------------------- &n

请问sin(pi),sin(pi/2)这样的数是等于多少啊?请问sin(pi),sin(pi/2),sin(pi/4),cos(pi),cos(pi/2),cos(pi/4),tan.cot...sec...csc等各为多少啊?sin和co

sin(11*pi/3)=?sin(11*pi/3)=sin(4π-π/3)=sin(-π/3)=-sinπ/3=-√3/2sin(11*pi/3)=sin(4pi-pi/3)=-sinpi/3=-根号3/2sin(11*pi/3)=sin

证明sin(pi/n)*sin(2pi/n)*sin(3pi/n)*…sin((n-1)pi/n)=n/(2^(n-1))用复数w=cos(2π/n)+isin(2π/n)w'=cos(2π/n)-isin(2π/n)z^n=1(z-1)(

求极限lim(1/n)*[(sin(pi/n)+sin(2pi/n)+.+sin(n*pi/n)]n->无穷用到积分的定义瓦晒，楼上是中学教师？我看是大学叫兽吧！点击放大，荧屏放大再放大：

[sin(3pi/10)sin(pi/10)]/[sin(3pi/10)-sin9pi/10)]化简.最好的方法就是用和差化积,积化和差公式,反复倒就能倒出来.

[sin(3pi/10)sin(pi/10)]/[sin(3pi/10)-sin9pi/10)]在线等化简.打错了。[sin(3pi/10)sin(pi/10)]/[sin(3pi/10)-sinpi/10)]最好的方法就是用和差化积,积化

利用matlab把xn=sin(0.2*pi*n)+sin(0.4*pi*n)+sin(0.6*pi*n)+randn(size(n))的随机信号去除,还会追加财富.有可能的话把三个正弦信号分开.下面是开头,往下接.其实xn只要是三个正弦信

化简间sin（a-2pi)cos(a+pi）tan(a-99pi)cos(pi-a)sin(3pi-a)sin（-a-pi）原式=sina(-cosa)tana(-cosa)sina(-sina)=-sin²acos²a

化简sin(2x-pi)sin[x+(3/2)pi]/cos[x+(5/2)pi][1-sin(pi+x)]sin(2x-pi)sin[x+(3/2)pi]/cos[x+(5/2)pi][1-sin(pi+x)]=(-sin2x)(cosx

matlaba=[pi/6pi/4;pi/33*pi/4];funm(a,'sin')ans=0.18640.07640.10180.3646怎么算?[4cos2;(-15π/4+4π)]/[tan(-11π/3+4π)+√2sin(25π

化简三角函数[sin(α+pi)*cos(pi+α)*cos(α+2pi)]/[tan(pi+α)*cos^3(-α-pi)][sin(α+pi)*cos(pi+α)*cos(α+2pi)]/[tan(pi+α)*cos^3(-α-pi)]

a*sin(pi/4-x)-b*cos(pi/4-x)=a*sin(pi/4+x)-b*cos(pi/4+x)怎么得到（a+b）*sinx=0asinπ/4cosx-acosπ/4sinx-bcosπ/4cosx-bsinπ/4sinx=a

sin(pi*t)/(pi*t)怎么用matlab实现什么意思,说清楚

sin(PI()X)+cos(pi()x)的周期sinπx+cosπx=根号2*sin(πx+π/4)所以T=2π/π=2sin(PI()X)+cos(pi()x)=根号2（cos45sin(PI()X)+sin45cos(pi()x)）=

用matlab绘出sin(pi*t)/(pi*t)弦波图matlab有定义sinc(x)=sin(pi*t)/(pi*t);clear;dt=0.001;Length=3;t=-3:dt:Length;xa=sinc(t);plot(t,x

sinpi/12-根号3cospi/12=解sinπ/12-√3cosπ/12=2(1/2sinπ/12-√3/2cosπ/12)=2sin（π/12-π/3)=2sin（-π/4）=-2sin（π/4）=-2×√2/2=-√2.

sin(3x+pi/3)的周期pi是派y=sin(wx+t)的周期是T=2∏/w所以这个的周期就是2∏/3T=2π/3.温馨提示：一般地，正弦型函数y=Asinx（ωx+φ）（A≠0，ω≠0）的周期只与x的系数ω有关，即周期T=2π/｜ω｜