已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及函数f(x)的解析式(2)若△ABC的三条边a,b,c满
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![已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及函数f(x)的解析式(2)若△ABC的三条边a,b,c满](/uploads/image/z/981809-17-9.jpg?t=%E5%B7%B2%E7%9F%A5%E5%87%BD%E6%95%B0f%28x%29%3D%E6%A0%B9%E5%8F%B73sinwx%C3%97coswx-cos%5E2wx%28w%EF%BC%9E0%EF%BC%89%E6%9C%80%E5%B0%8F%E6%AD%A3%E5%91%A8%E6%9C%9F%E4%B8%BA%CF%80%2F2%EF%BC%881%EF%BC%89%E6%B1%82w%E7%9A%84%E5%80%BC%E5%8F%8A%E5%B7%B2%E7%9F%A5%E5%87%BD%E6%95%B0f%28x%29%3D%E6%A0%B9%E5%8F%B73sinwx%C3%97coswx-cos%5E2wx%28w%EF%BC%9E0%EF%BC%89%E6%9C%80%E5%B0%8F%E6%AD%A3%E5%91%A8%E6%9C%9F%E4%B8%BA%CF%80%2F2%EF%BC%881%EF%BC%89%E6%B1%82w%E7%9A%84%E5%80%BC%E5%8F%8A%E5%87%BD%E6%95%B0f%28x%29%E7%9A%84%E8%A7%A3%E6%9E%90%E5%BC%8F%EF%BC%882%EF%BC%89%E8%8B%A5%E2%96%B3ABC%E7%9A%84%E4%B8%89%E6%9D%A1%E8%BE%B9a%2Cb%2Cc%E6%BB%A1)
已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及函数f(x)的解析式(2)若△ABC的三条边a,b,c满
已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及
已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(
1)求w的值及函数f(x)的解析式
(2)若△ABC的三条边a,b,c满足a^2=bc,a边所对的角为A,求A的取值范围
cos^2wx 是 coswx 的平方
已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)最小正周期为π/2(1)求w的值及函数f(x)的解析式(2)若△ABC的三条边a,b,c满
1.已知函数f(x)=根号3sinwx×coswx-cos^2wx(w>0)
=√3/2sin2wx-1/2cos2wx-1/2
=sin(2wx-π/6)-1/2
最小正周期为π/2
最小正周期为2π/2w=π/2 w=2
f(x)==sin(4x-π/6)-1/2
2.若△ABC的三条边a,b,c满足a^2=bc
余弦定理
cosA=(b^2+c^2-a^2)/2bc=(b^2+c^2-cb)/2bc b^2+c^2>=2bc
>=bc/2bc
=1/2
cosA>=1/2
y=cosx在(0,π)上是减函数
所以 0
f(x) = √3*sinwx*coswx-cos^2wx
=√3/2*sin2wx-1/2*cos2wx-1/2
=sin(2wx-π/6)-1/2
∵周期为二分之派
∴2π/2w=π/2
∴w=2
f(x) =sin(4x-π/6)-1/2
∴单调增区间:-π/2+2kπ≤4x-π/6≤π/2+2kπ
∴单调增区间...
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f(x) = √3*sinwx*coswx-cos^2wx
=√3/2*sin2wx-1/2*cos2wx-1/2
=sin(2wx-π/6)-1/2
∵周期为二分之派
∴2π/2w=π/2
∴w=2
f(x) =sin(4x-π/6)-1/2
∴单调增区间:-π/2+2kπ≤4x-π/6≤π/2+2kπ
∴单调增区间:-π/12+kπ/2≤x≤π/6+kπ/2
` 单调减区间:π/6+kπ/2≤x≤(5/12)π+kπ/2
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