3sinx-√3cosx=2√3sin(x+b),b是?3sinx-√3cosx=2√3sin(x+b),b属于(-π,π),b是?

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3sinx-√3cosx=2√3sin(x+b),b是?3sinx-√3cosx=2√3sin(x+b),b属于(-π,π),b是?

3sinx-√3cosx=2√3sin(x+b),b是?3sinx-√3cosx=2√3sin(x+b),b属于(-π,π),b是?
3sinx-√3cosx=2√3sin(x+b),b是?
3sinx-√3cosx=2√3sin(x+b),b属于(-π,π),b是?

3sinx-√3cosx=2√3sin(x+b),b是?3sinx-√3cosx=2√3sin(x+b),b属于(-π,π),b是?
3sinx-√3cosx
=2√3(√3/2*sinx-1/2*cosx)
=2√3(sinxcosπ/6-cosxsinπ/6)
=2√3sin(x-π/6)
=2√3sin(x+b)
sin(x-π/6)=sin(x+b)
所以x-π/6=2kπ+x+b或x-π/6=2kπ+π-x-b
x-π/6=2kπ+x+b
-π/6=2kπ+b
b=-π/6-2kπ
所以k=0
b=-π/6
x-π/6=2kπ+π-x-b
这个不是恒等式
所以
b=-π/6

xsin A+ ycosA=√(x^2+y^2) sin(A+T),
其中 tan T= y/x
b=arc tan ((-√3) /3) =-π/6

-π/6

3sinx-√3cosx=2√3sin(x+b),
(√3/2sinx-1/2cosx)=sin(x+b),
sin(x-π/6)=sin(x+b),b=-π/6