2sin平方x+3sinxcosx-cos平方x
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/06 12:00:00
稍等再答:sin(π/3-x)=sin[π/2-(x+π/6)]=cos(x+π/6)所以原式=1再答:快采纳
f(x)=(sin²x+cos²x)+(√3/2)(2sinxcosx)+cos²x=1+(√3/2)sin2x+(1+cos2x)/2=(√3/2)sin2x+(1/2
1.(1)f(x)=cos(2x+π/3)+sin(平方)x=1/2cos2x-根号3/2sin2x+sin(平方)x+1/2-1/2=1/2cos2x-根号3/2sin2x-1/2cos2x+1/2
f(x)=2cosx*sin(x+π/3)-√3sinx^2+sinx*cosx=2cosx*(sinxcosπ/3+cosxsinπ/3))-√3sinx^2+sinx*cosx=sinxcosx+
函数y=(sinx+cosx)平方+2sin平方x=1+2sinxcosx+2sin^2x=sin2x-cos2x+2=√2sin(2x-π/4)+2
f(x)=sin²(x)+(√3)sin(x)cos(x)+2cos²(x)=3/2+√3/2sin2x+1/2cos2x=3/2+sin(2x+π/6)函数f(x)的最小正周期T
6sin^2(x)+sinxcosx-2cos^2(x)=0因式分解(2sinx-cosx)(3sinx+2cosx)=0因x∈[π/2,π]而此时sinx≥0,cosx≤0因此,只可能是(3sinx
y=sinx^2+根3sinxcosx+2cosx^2=-1/2(1-2sinx^2)+1/2根3*2sinxcosx+2cosx^2-1+3/2=-1/2cos2x+二分之根3倍sin2x+cos2
f(x)=2√3sin²x-sin(2x-π/3)=√3-√3cos2x-1/2sin2x+√3/2cos2x=√3-(1/2sin2x+√3/2cos2x)=√3-sin(2x+π/3)T
1.√3sinx+cosx=2*(sinx*√3/2+cosx/2)=2(sinxcosπ/6+cosxsinπ/6)=2sin(x+π/6)2.用万能公式可得字数受限
f(x)=3sin平方x+2根号3sinxcosx-3cos平方x=根号3sin2x-3cos2x=2根号3sin(2x-π/3)
前提掌握:sinx*sinx+cosx*cosx=1cos2x=2*cosx*cosx-1=1-2*sinx*sinxcos(x-π/4)=-sin(x-π/4+π/2)=-sin(x+π/4)sin
y=2cosX*[sinXcospai/3+cosXsinpai/3]-根号3sin平方X+sinX·cosX=2cosX(1/2sinX+√3/2cosX)-根号3sin平方X+sinX·cosX=
sin^2x=1-cos^2x
f(x)=sin²x+√3sinx*sin(x+π/2)=sin²x+√3sinxcosx=(1/2)(1-cos2x)+(√3/2)sin2x=(√3/2)sin2x-(1/2)
y=sin平方(2x-3)=(1-cos(4x-6))/2=0.5-0.5cos(2x-3)y'=2sin(2x-3)*cos(2x-3)*2=4sin(2x-3)*cos(2x-3)楼主,给分.
答:sin^2a+sin^2(a+60)+sin^2(a+120)=3/2.证明:左边=sin^2a+sin^2(a+60)+sin^2(a+120)=sin^2a+(sinacos60+cosasi
sin的平方1度+sin的平方2度+sin的平方3度+.+sin的平方89度=sin^2(90-89)+sin^2(90-88)+sin^2(90-87)+.+sin^2(89)=cos^2(89)+
因式分解为(sinX-1/2)^2+11/4你把原题放出来,那就简单了,sinx的定义域是(-1,1)之间,所以(sinX-1/2)^2的最大值是9/4,最小值是0,所以Y的最大值是9/4+11/4=