答案是错误的,错误在于只看sinx的增区间,而没考虑sin(-x)的增区间,而者却是相反.
0
0<2x<2π
-π/6<2x-π/6<11π/6
y=2sin(π/6-2x)=-2sin(2x-π/6)
y增函数的区间是sin(2x-π/6)的减区间
π/2<2x-π/6<3π/2
π/3
答案是错误的,错误在于只看sinx的增区间,而没考虑sin(-x)的增区间,而者却是相反.
0
0<2x<2π
-π/6<2x-π/6<11π/6
y=2sin(π/6-2x)=-2sin(2x-π/6)
y增函数的区间是sin(2x-π/6)的减区间
π/2<2x-π/6<3π/2
π/3