3sinx cosx=2sin(x 6)

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已知函数f(x)=2cosxsin(x+60°)-根号3sin^2x+sinxcosx

f(x)=2cosxsin(x+60°)-√3sin²x+sinxcosx=2cosx(sinxcos60º+cosxsin60º)-√3sin²x+sinxc

已知函数f(x)=cos^2x-sin^2x+2根号3sinxcosx+1

f(x)=cos^2x-sin^2x+2(根号3)sinxcosx+1=cos2x+(根号3)sin2x+1=2{(1/2)cos2x+[(根号3)/2]sin2x}+1=2sin(2x+派/6)+1

已知函数f(x)=3/2--3sin^2x--√3sinxcosx

f(x)=3/2-3sin^2x-√3sinxcosx=3/2-3*(1-cos2x)/2-(√3/2)*sin2x=(3/2)*cos2x-(√3/2)*sin2x=√3*[(√3/2)*cos2x

已知函数f(x)=根号3(sin^2x-cos^2x)-2sinxcosx

f(x)=√3(sin^2x-cos^2x)-2sinxcosx=-√3cos2x-sin2x=-2sin(2x+π/3)1.求最小正周期T=π2.设x∈[-π/3,π/3],求函数的值域和单调区间-

已知函数f(x)=sin^2x-2sinxcosx+3cos^2x

f(x)=sin^2x-2sinxcosx+3cos^2x=sin^2x+cos^2x-2sinxcosx+2cos^2x=1-sin2x+2cos^2x=cos2x-sin2x+2=√2cos(2x

已知函数f(x)=sin^2x+2sinxcosx+3cos^2x

f(x)=sin^2x+2sinxcosx+3cos^2x=1+sin2x+2cos²x=2+sin2x+cos2x=2+√2sin(2x+π/4)所以f(x)周期为Kπ(2)先纵向拉长√2

已知函数f(x)=-√3sin^2x+sinxcosx+√3/2

f(x)=-√3sin2x+1/2sin2x+√3/2=(-√3+1/2)sin2x+√3/2因为sin2x的最小正周期为2π/2=π因为-√3+1/2小于0所以单调递增区间为(π/4+kπ,3π/4

sin^2x+2sinxcosx-3cos^2x=1 求sinx

sin^2x+2sinxcosx-3cos^2x=12sinxcosx-4cos^2x=0sinxcosx=2cos^2xcosx(sinx-2cosx)=0(1)cosx=0,sinx=±1(2)s

已知tanx=-0.5,求sin^2x+2sinxcosx-3cos^2x的值,

除以cos^2x得原式=tan^2x+2tanx-3=-15/4

已知函数y=2cosxsin(x+π/3)-根号3 *(sin^2) x +sinxcosx

y=2cosxsin(x+π/3)-根号3*(sin^2)x+sinxcosx,后两项先提出一个sinx,然后括号内部分用叠加原理,得到y=2cosxsin(x+π/3)+2sinxcos(x+π/3

已知函数f(x)=-2sin^2x+2根号3sinxcosx+1

sin^2X=1/2-(1/2)cos(2X))sof(x)=-1+cos(2x)+sqrt(3)sin2x+1=2sin(2x+pi/6)whenxbelongsto-pi/6,pi/3,2x+pi

y=1/2cos^2x+sinxcosx+3/2sin^2x 求单调区间

hiy=1/2cos^2x+sinxcosx+3/2sin^2x=1/2*((1+cos2x)/2)+1/2*sin2x+3/2*((1+cos2x)/2)=1/2*sin2x-1/2*cos2x+1

已知sinx+2cosx=0,则2sin*x-3sinxcosx=?

sinx+2cosx=0sinx=-2cosxsin²x+cos²x=15cos²x=1cos²x=1/52sin²x-3sinxcosx=8cos&

已知函数f(x)=-2sin^2+2根号3x 2sinxcosx+1

1、∵1-cos2x=2sin^2∴f(x)=2sinxsinx+2√3sinxcosx+1=1-cos2x+√3sin2x+1=2+2(√3/2*sin2x-1/2*cos2x)=2(cos(π/6

已知函数f(x)=2sin^2+2根号3x 2sinxcosx+1

1、f(x)=2sinxsinx+2√3sinxcosx+1=1-cos2x+√3sin2x+1=2sin(2x-π/6)+2对称轴:2x-π/6=kπ+π/2,得x=kπ/2+π/3对称中心:2x-

解方程:sin^2x+2sinxcosx-3cos^3x=-2

移项sin^2x+2sinxcosx-3cos^2x+2=0sin^2x+2sinxcosx-3cos^2x+2(sin^2x+cos^2x)=03sin^2x+2sinxcosx-cos^2x=0(

已知tanX=2求2sin^2X+sinXcosX-3cos^2X

万能公式知道吧是要记的哦...sin2x=2tanx/(1+tan^2x)=4/5cos2x=(1-tan^2x)/(1+tan^2x)=-3/5原式=2sin^2x-1+1+sin2x/2-3(2c

函数f(x)=2cosxsin(x+π/3)-根号3sin²x+sinxcosx

最大值2,最小值-2.通过化简,化成一个三角函数式,即可知道结果.请参考图片.

已知函数f(x)=2根号3sinxcosx+2sin^2x-1,x

f(x)=√3sin2x+(1-cos2x)-1=√3sin2x-cos2x=2sin(2x-π/6)最小正周期T=2π/2=π单调增区间:2kπ-π/2=