急...求导y=2x乘以cos(2x+π/6)
问题描述:
急...求导y=2x乘以cos(2x+π/6)
答
y=2xcos(2x+π/6)
y'=2cos(2x+π/6)-2xsin(2x+π/6)*2
=2cos(2x+π/6)-4xsin(2x+π/6)
答
y'=(2x)' cos(2x+π/6)+2x[cos(2x+π/6)]'
=2cos(2x+π/6) - 4xsin(2x+π/6)