函数fx=sinX cosX的最大值
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f(x)=2cos²x+2√3sinxcosx=1+cos(2x)+√3sin(2x)=2[(√3/2)sin(2x)+(1/2)cos(2x)]+1=2sin(2x+π/6)+1当sin(
f(x)=-√3sin²x+sinxcosx=√3/2cos2x+1/2sin2x-1/2=sin(2x+π/3)+1/2T=2π/2=πf(π/6)=sin(π/3+π/3)+1/2=(1
f(x)=a(cos²x+sinxcosx)+b=a(cos²x-1/2+sinxcosx+1/2)+b=a(cos2x/2+sin2x/2)+b=a根号下2sin(2x+π/4)
f(x)=cos2x+根号3sin2x=2sin(2x+π/2)所以周期为π对称轴2x+π/2=π/2+kπ(k是整数)即x=kπ/2k是整数单调区间-π/2+2kπ
f(x)=1/2-1/2cos2x+√3/2sin2x-1/2=sin(2x-π/6)f(-π/12)=sin(-π/3)=-√3/2(2)-π/6
f(x)=2√3sinxcosx+2sin^2x-1=√3sin2x-cos2x=2sin(2x-π/6)最小正周期T=π,单调递增区间:2kπ-π/2
f(x)=sin²x+√3sinxcosx+2cos²x,=√3sinxcosx+cos²x+1=√3/2sin2x+1/2(1+cos2x)+1=√3/2sin2x+1
f(x)=√3sin2x+cos2x=2(sin2x*√3/2+cos2x*1/2)=2(sin2xcosπ/6+cos2xsinπ/6)=2sin(2x+π/6)所以f(π/6)=2sin(2×π/
fx=2cos^2x+2根号3sinxcosx-1=2cos^2x-1+2根号3sinxcosx根据倍角公式,sin2α=2sinαcosαcos2α=2cos^2(α)-1fx=cos2x+根号3s
1.T=πfx=2cosxsin(x+π/3)-√3sin^2x+sinxcosx=cosxsinx+√3cos^2x-√3sin^2x+sinxcosx=2sinxcosx+√3cos2x=sin2
f(x)=(2sinxcosx)/2=(sin2x)/2周期为2π/2=π最小值为-1/2,sin2x=-1时取得
fx=2√3sinxcosx+2cos^2x-1=√3sin2x+cos2x=2(√3/2sin2x+1/2cos2x)=2sin(2x+π/6)所以最小正周期是π建议你再看看二倍角公式
f(x)=cos²x+sinxcosx=(cos2x+1)/2+1/2sin2x=(1/2cos2x+1/2sin2x)+1/2=√2/2*(√2/2cos2x+√2/2sin2x)+1/2
y=sin^4(x)+2√3(sinxcosx)-cos^4(x)=sin^4(x)-cos^4(x)+2√3sinxcosx=(sin^2x+cos^2x)(sin^2x-cos^2x)+2√3(s
f(x)=2sinxcosx-(2cos²x-1)=sin2x-cos2x=√2sin(2x-π/4)所以值域是[-√2,√2]
已知函数fx=√3sinxcosx+(cos∧2)x+a(1)求fx的最小正周期及单调递减区间(2)若fx在区间[~π/6,π/3]上的最大值与最小值的和为3/2,求a的值.(1)解析:f(x)=√3
解f(x)=2cos^2x+2√3sinxcosx-1=√3sin2x+cos2x=2sin(2x+π/6)∴最小正周期为:2π/2=π再答:不懂追问再问:在三角形ABC中,角ABC所对的边分别是ab
函数fx=2根号3sinxcosx+1-2sinX=根号3sin2x+cos2x=2sin(2x+30度),fx的值域就是【-2,2】
f(x)=sin2x+cos2x=√2sin(2x+π/4)最小正周期T=2π/2=π最大值为√2再问:题目都不一样再答:哪不一样?2sinxcosx可化为sin2x呀。