简单数学题求函数f(x)=sin^X+根号3sinXcosX+2cos^2X,(X属于R),求函数的最小正周期是?(过程要详细)
问题描述:
简单数学题求函数f(x)=sin^X+根号3sinXcosX+2cos^2X,(X属于R),求函数的最小正周期是?(过程要详细)
答
f(x)=sin²X + √3sinXcosX + 2cos²X
=(sin²X + cos²X) + (√3/2)×2sinXcosX + cos²X
=1 + (√3/2)sin2X + cos²X
=(√3/2)sin2X + (1+cos2X)/2 + 1
=(√3/2)sin2X + (1/2)cos2X + 3/2
=√[(√3/2)² + (1/2)²] × sin(2X + π/6) + 3/2
=sin(2X + π/6) + 3/2
T=2π/2=π