已知函数fx =2sin(x-6分之派 )cosx+2cos平方x

f(x)=2sin(x-π/6)cosx+2cos²x=(2sinxcosπ/6-2cosxsinπ/6)cosx+2cos²x=√3sinxcosx-cos²x+2cos²x=√3sinxcosx+cos²x=2(√3/2sinx+1/2cosx)cosx=2six(x+π/6)cosx=sin(2x+π/6)+sinπ/6=s...