已知函数y=根号2cos(2x-4分之x)

y=1/2cos²x+（根号3）/2sinxcosx+1=(1/2)*(cos2x+1)/2+（根号3）/4*sin2x+1=(1/2)*[cos2x*(1/2)+sin2x*根号3/2]+

y=根号3cos²x+sinxcosx-根号3/2=√3（1/2cos2x+1/2)+1/2sin2x-√3/2=√3/2cos2x+√3/2+1/2sin2x-√3/2=√3/2cos2x

已知:函数f(x)=2sinxcosx+2√3cos²x-√3求:(1)单调增区间和最小正周期；(2)当x∈[-π/4,π/4]时求最值.f(x)=2sinxcosx+2√3cos²

f(x)=2sinxcosx+2√3cos²x-√3=2sinxcosx+√3(2cos²x-1)=sin2x+√3cos2x=2sin(2x+π/3)最小正周期T=2π/2=π,

1/2=sin(π/6),√3/2=cos(π/6),因此可对表达式化简：y=(1/2)(cosx)^2+(√3/2)sinxcosx+1=cosx[sin(π/6)cosx+cos(π/6)sinx

y=2√3sinxcosx+2cos²x=√3sin2x+cos2x+1=2(√3/2sin2x+1/2*cos2x)+1=2(sin2xcosπ/6+cos2xsinπ/6)+1=2sin

y=(sinx+cosx)^2+2cos^x=2+sin2x+cos2x=2+√2sin(2x+π/4)ymax=2+√2,ymin=2-√2.2kπ+π/2≤2x+π/4≤2kπ+3π/22kπ+π

y=1/2cos²x+√3/2sinxcosx+1=1/2(1/2+1/2cos2x+√3/2sin2x)+1=1/2(sin2xcosπ/6+cos2xsinπ/6)+1+1/4=1/2s

1．y=1/4(1+cos2x)+√3/4sin2x+1=1/2sin(2x+π/6)+5/4当2x+π/6＝2kπ+π/2,即x＝kπ＋π/6时,ymax＝7/4.自变量x的集合{x│x＝kπ＋π/

（1）原式=2[(1/2)sin(x/2)+（根号3/2）cos(x/2)]=2sin[(x/2)+pi/3]所以当[(x/2)+pi/3]=2kpi+pi/2时,y最大值为2解得x=4kpi+pi/

f(x)=sin2x-2√3(cosx)^2+√3=sin2x-√3(1+cos2x)+√3=sin2x-√3cos2x=2sin(2x-π/3)π/4=再问：π/6=

y=2根号3sinxcosx-2cos^2x+1＝根号3sin2x-cos2x=2sin(2x-π/6)T=2π/2=π2x-π/6=2kπ+π/2当x=kπ+π/3时,函数的最大值=22x-π/6=

-3

y=2（2cos²x-1）+2倍根号三sin2xy=2cos2x+2倍根号三sin2xy=4（1/2倍cos2x+根号三/2倍sin2x）y=4sin（π/6+2x）三角函数解析式有了想要什

Y=4(cos⁡x)^2+4√3sin⁡xcos⁡x-2=2cos⁡2x+4√3sin⁡xcos⁡x=4sin⁡〖(

已知函数y=sin^2x+2根号3sinxcosx-cos^x=根号3sin2x-cos2x=2sin(2x-π/6)（1）求函数y的最大值,并求y取最大值时,自变量x的集合ymax=22x-π/6=

解y=2cos^2x+2根号3sinxcosx-1=（1+cos2x）+√3sin2x-1=cos2x+√3sin2x=2（√3/2sin2x+1/2cos2x）=2sin（2x+π/6）即T=2π/

f(x)=sinxcosx+√3(cosx)^2-√3/2=(1/2)sin2x+(√3/2)cos2x=sin2xcosπ/3+cos2xsinπ/3=sin(2x+π/3)1.0

f（x）=√3cos²x+sinxcosx-√3/2=√3(cos2x+1)/2+sin2x/2-√3/2=√3/2cos2x+√3/2+1/2sin2x-√3/2=1/2sin2x+√3/