求下列函数值域,①y﹦cosx②y﹦cosx,x∈[-π/2,π/2]③y﹦cosx,x∈[-π/3,π]④y﹦2sin（2x-π/3）﹢1⑤y﹦2sin（2x-π/3）﹢1,x∈[π/3,π]

求下列函数值域,①y﹦cosx②y﹦cosx,x∈[-π/2,π/2]③y﹦cosx,x∈[-π/3,π]④y﹦2sin（2x-π/3）﹢1⑤y﹦2sin（2x-π/3）﹢1,x∈[π/3,π]
求下列函数值域,
①y﹦cosx②y﹦cosx,x∈[-π/2,π/2]③y﹦cosx,x∈[-π/3,π]④y﹦2sin（2x-π/3）﹢1⑤y﹦2sin（2x-π/3）﹢1,x∈[π/3,π]

求下列函数值域,①y﹦cosx②y﹦cosx,x∈[-π/2,π/2]③y﹦cosx,x∈[-π/3,π]④y﹦2sin（2x-π/3）﹢1⑤y﹦2sin（2x-π/3）﹢1,x∈[π/3,π]
①y﹦cosx
值域为[-1,1]
②y﹦cosx,x∈[-π/2,π/2]
值域为[0,1]
③y﹦cosx,x∈[-π/3,π]
值域为[-1,1]
④y﹦2sin（2x-π/3）﹢1
值域为[-1,3]
⑤y﹦2sin（2x-π/3）﹢1,x∈[π/3,π]
2x-π/3的范围为 [π/3,5π/3]
所以 2sin(2x-π/3)的范围为[-1,1]
值域为[-1,3]