已知向量m=（2sinx,cosx）,n=（根号3cosx,2cosx）,定义函数fx=m*n-1 （1）求fx最小正周

f(x)=m*n-1=2sinx*√3cosx+cosx*2cosx-1=2√3sinxcosx+2(cosx)^2-1=√3sin2x+cos2x=2(√3/2*sin2x+1/2*cos2x)=2(sin2xcosπ/6+cos2xsinπ/6)=2sin(2x+π/6)T=2π/2=π2kπ-π/2