(1)求函数f(x)的最小正周期
(2)若存在x∈【0,5π/12】,使不等式f(x)>m成立,求实数m的取值范围
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已知函数f(x)=2cosxsin(x+π\/3)+sinxcosx-√3sin²x,x∈R
sinxcosx+√3(cos²x-sin²x)=sin2x+√3cos2x =2sin(2x+π\/3)(1)最小正周期 =2π\/2=π (2)x∈[0,5π\/12]2x+π\/3∈[π\/3,7π\/6]sin(2x+π\/3)∈[-1\/2,1]2sin(2x+π\/3)∈[-1,2]f(x)>m成立 m<-1 如果您认可我的回答,请点击“采纳为满意答案”,...
已知函数f(x)=2cosxsin(x+π\/3)-√3sin²x+sinxcosx(x属于R)
当2x+(π\/3)=3π\/2时,函数f(x)有最小值且f(x)=-2,此时,x=7π\/12;又∵sinx的单调减区间为:2kπ+(π\/2)≤x≤2kπ+(3π\/2);∴2kπ+(π\/2)≤2x+(π\/3)≤2kπ+(3π\/2)解之得:kπ+(π\/12)≤x≤kπ+(7π\/12)
已知函数f(x)=2cosxsin(x+π\/3)+sin(cosx﹣√3sinx)求最小正周期
f(x)=2cosxsin(x+π\/3)+sinx(cosx-√3sinx)=2cosxsinxcosπ\/3+2cos^2xsinπ\/3+sinxcosx-√3sin^2x =sin2x*1\/2+(cos2x-1)*√3\/2+1\/2sin2x-√3\/2(1-cos2x)=sin2x+√3cos2x-√3 =2(1\/2sin2x+√3\/2cos2x)-√3 =2sin(2x+π\/3)-√3 T=2π\/2=π ...
已知函数f(x)=2cosx*sin(x+π\/3)-根号3sin^x+sinxcosx 1.求函数f...
=sinxcosx+√3*cos²x-√3sin²x+sinxcosx =2sinxcosx+√3(cos²x-sin²x)=sin2x+√3cos2x =2(1\/2*sin2x+√3\/2*cos2x)=2sin(2x+π\/3)(1)令2kπ+π\/2≤2x+π\/3≤2kπ+3π\/2 解得:kπ+π\/12≤x≤2kπ+7π\/12 所以f(x)的单调递减区间集合为[k...
已知函数f(x)=2cosxsin(x+π\/3)-根号3sin^2x+sinxcosx+2(x∈R),
f(x)=sinxcosx+sqrt(3)(cosx)^2-sqrt(3)(sinx)^2+sinxcosx+2 =2sinxcosx+sqrt(3)[(cosx)^2-(sinx)^2]=sin2x+sqrt(3)cos2x =2sin(2x+π\/3)所以最小正周期是π 单调增区间[-5π\/12+kπ,π\/12+kπ],k是整数。
f(x)=2cosxsin(x+π\/3)-根3sinx平方
f(x)=2cosxsin(x+π\/3)- √3sin²x+sinxcosx =sin(2x+π\/3)+sin(π\/3)-(√3\/2)(1-cos2x)+(1\/2)sin2x = sin(2x+π\/3) +(1\/2)sin2x+(√3\/2) cos2x = sin(2x+π\/3) + sin(2x+π\/3)= 2sin(2x+π\/3)当x∈[0,π\/2]时,2x+π\/3∈[π\/3,4π\/3]∴...
已知函数f(x)=2cosxsin(x+π\/3)-根号3sin^2x+sinxcosx,求方程f(x...
=2sin(2x+π\/3)=x\/50π,<==>sin(2x+π\/3)=x\/100π,由于|sin(2x+π\/3)|<=1,所以只需考虑|x|<=100π,即-100π<=x<=100π.200π是sin(2x+π\/3)的200个周期,画示意图知,y=sin(2x+π\/3)最右边的一个周期的图像与直线y=x\/100π只有1个交点,其他199个周期的图像与直...
【数学】已知函数f(x)=2cosxsin(x+π\/3)-√3sin^2(x)+sinxcosx
=sin2x+√3cos2x =2sin[2x+(π\/3)]所以:①最小正周期T=2π\/2=π ②最大值=2,最小值=-2 ③递增区间为2x+(π\/3)∈[2kπ-(π\/2),2kπ+(π\/2)]===> 2x∈[2kπ-(5π\/6),2kπ+(π\/6)]===> x∈[kπ-(5π\/12),kπ+(π\/12)](k∈Z)④f(x)=x\/(50π)根...
已知函数f(x)=2cosxsin(x+π\/3)-^3sin2x+sinxcosx
解:f(x)=2cosxsin(x+ π3)- 3(sinx)2+sinxcosx=2cosx(sin x2+ 3cos x2)- 31-cos2x2+ 12sin2x =sinxcosx+ 31-cosx2- 32+ 3cos2x2+ sin2x2 =sin2x+ 3cos2x =2sin(2x+ π3)
已知函数f(x)=2sin(x-π\/3)cosx+sinxcosx+√3sin^2x(x属于R),
f(x)=2sin(x-π\/3)cosx+sinxcosx+√3sin^2x =2(sinxcosπ\/3-cosxsinπ\/3)cosx+sinxcosx+√3sin^2x =sinxcosx-√3cos^2x+sinxcosx+√3sin^2x =2sinxcosx-√3(cos^2x-sin^2x)=sin2x-√3cos2x =2(1\/2sin2x-√3\/2cos2x)=2sin(2x-π\/3)由2kπ-π\/2≤2x-π\/3≤2kπ...