sinx 根号3cosx=a有两个不等的实数根,求a的范围
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解a=(2√3sinx,cosx+sinx),b=(cosx,cosx-sinx)f(x)=a·b=2√3sinxcosx+cos^2x-sin^2x=√3sin2x+cos2x=2sin(2x+π/
解:a.b=2√3sinx*cosx+(cos+sinx)(cosx-sinx)=√3sin2x+cos²x-sin²xa.b=√3sin2x+cos2x=2sin(2x+π/6)
/>tanx=√3则x=kπ+π/3,k∈Z(1)k是偶数,则sinx=√3/2,cosx=1/2(2)k是奇数则sinx=√3/2,cosx=1/2(sinx+cosx)/(sinx-cosx)的值
用sinx2+cosx2=1再问:可以帮我把顺序写出吗。再问:谢谢。再答:就是3cos2x+cos2x=1再答:然后cosx=正负0.5就行了再问:就只有后面这两个步骤吧再问:还是前面那个也要再问:s
sinx+根号3cosx=2sin(x+π/3)=a则sin(x+π/3)=a/2∵0≤x≤π/2所以π/3≤x+π/3≤5π/6∴也就是正弦函数sinx在[π/3,5π/6]范围内有两个值的画图可以
sinx+根号3cosx=2sin(x+π/3)=a则sin(x+π/3)=a/2∵0≤x≤π/2所以π/3≤x+π/3≤5π/6∴也就是正弦函数sinx在[π/3,5π/6]范围内有两个值的画图可以
sinx+根号3cosx=22(sinx/2+根号3cosx/2)=2sinx/2+根号3cosx/2=1sinxcosπ/3+cosxsinπ/3=1sin(x+π/3)=1所以x+π/3=2kπ+
f(x)=a^2+2aba^2=1,a*b=(sinx)^2+√3sinx*cosx=1/2-1/2cos2x+√3/2sin(2x)=1/2+sin(2x-π/6)所以f(x)=1+2(1/2+si
f(x)=(2sinx)×(√3cosx)+(cosx+sinx)×(sinx-cosx)f(x)=2√3sinxcosx-(cos²x-sin²x)f(x)=√3sin2x-co
f(x)=ab=2√3sinxcosx+cos²x-sin²x=√3sin2x+cos2x.正弦,余弦二倍角公式=2(√3/2*sin2x+1/2*cos2x)=2sin(2x+π
f(x)=mn=2cos^2x+2√3sinxcosx+a-1+1=cos2x+√3sin2x+a+1=2sin(2x+π/6)+a+1f(x)=0sin(2x+π/6)=(-a-1)/2f(x)在【
1.f(x)=2(√3sinxcosx+(cosx)^2)+2m-1=√3sin2x+cos2x+2m=2sin(2x+pi/6)+2m最小正周期=pi2.x属于[0,pi/2]f(x)最小值=2si
(1)解析:函数f(x)=√3cos²x+sinxcosx=√3(cos2x+1)/2+1/2sin2x=sin(2x+π/6)+√3则函数的最小正周期为π,图像的对称轴方程x=kπ+π/6
(1)a*b=0sin2x-cos2x=0sqr(2)sin(2x-π/4)=0x=π/8+kπ/2,k∈Z(2)f(x)=sqr(2)sin(2x-π/4)x∈(3π/8+kπ,7π/8+kπ),k
y=√3cosx+sinx=2[(√3/2)cosx+(1/2)sinx]=2(sinπ/3cosx+cosπ/3sinx)=2sin(x+π/3)所以它的最小正周期=2π;图像的对称轴为:x=kπ+
不用画图值域就是[-2,2]因为y=cosx的值域是[-1,1]
A∈〖-2,2〗X1=7/6∏X2=∏/6
没错,f(x)=2sin(2x+π/6)周期T=2π/2=π因为-1≤sin(2x+π/6)≤1f(x)max=2f(x)min=-2
f(x)=a·b=sin²x-√3sinxcosx²=1/2-(cos2x+√3sin2x)/2=1/2-sin(2x+π/6)单调递增区间2x+π/6∈[(2n+1/2)π,(2
向量a=(√3cosx,cosx),b=(0,sinx),c=(sinx,cosx),d=(sinx,sinx)(1)c•d=sin²x+sinxcosx=(1-cos2x)/2