求此三角恒等变换数学题答案y=sin2x+sin(2x+派/3)/cos2x+cos(2x+派/3)的最小正周期

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求此三角恒等变换数学题答案y=sin2x+sin(2x+派/3)/cos2x+cos(2x+派/3)的最小正周期
求此三角恒等变换数学题答案
y=sin2x+sin(2x+派/3)/cos2x+cos(2x+派/3)的最小正周期

求此三角恒等变换数学题答案y=sin2x+sin(2x+派/3)/cos2x+cos(2x+派/3)的最小正周期
是y=[sin2x+sin(2x+π/3)]/[cos2x+cos(2x+π/3)]吧!
y=[sin2x+sin(2x+π/3)]/[cos2x+cos(2x+π/3)]
=[sin2x+(1/2)sin2x+(√3/2)cos2x]/[cos2x+(1/2)cos2x-(√3/2)sin2x]
=[(3/2)sin2x+(√3/2)cos2x]/[(3/2)cos2x-(√3/2)sin2x]
=[(√3)sin2x+cos2x]/[(√3)cos2x-sin2x]
=2sin(2x+π/6)]/[2cos(2x+π/6)]
=tan(2x+π/6),
所以T=π/2.

原式=sin2x+[sin(2x+π/3]/cos2x+cos(2x+π/3)
=sin2x+[(1/2)sin2x+√3/2cos2x]/cos2x+cos(2x+π/3)
=sin2x+(1/2)tan2x+√3/2+cos(2x+π/3)
sin2x,cos(2x+π/3)周期为π,
tan2x的周期为π/2
所以,合周期还是π