函数y=2a cos平方x-2根3a sinx cosx+a+b(a

题目

函数y=2a cos平方x-2根3a sinx cosx+a+b(a

答案

y=a[(1+cos2x)-(√3)sin2x]+a+b=a[cos2x-(√3)sin2x]+2a+b
=2a[(1/2)cos2x-(√3/2)sin2x]+2a+b=2a[cos2xcos(π/3)-sin2xsin(π/3)]+2a+b
=2acos(2x+π/3)+2a+b (a