∵f(0)=2a=2
∴a=1
又∵f(π/3)=a/2+√3b/4=1/2+√3/2
∴b=2
f(x)=2cos²x+2sinxcosx=sin2x+cos2x+1=√2sin(2x+π/4)+1
当sin(2x+π/4)=-1时f(x)取得最小值1-√2
∵f(0)=2a=2
∴a=1
又∵f(π/3)=a/2+√3b/4=1/2+√3/2
∴b=2
f(x)=2cos²x+2sinxcosx=sin2x+cos2x+1=√2sin(2x+π/4)+1
当sin(2x+π/4)=-1时f(x)取得最小值1-√2