y'=4sin(2x+π/3)cos(2x+π/3) 化简 y'=2sin(4x+2π/3).怎么化简的?_数学解答

y'=4sin(2x+π/3)cos(2x+π/3) 化简 y'=2sin(4x+2π/3).怎么化简的?

人气：452 ℃　时间：2020-04-30 14:15:28

解答

三角函数倍角公式为：
sin2x=2sinxcosx
所以：
y'=4sin(2x+π/3)cos(2x+π/3)
=2sin2(2x+π/3)
=2sin(4x+2π/3)