高中数学函数定义域值域问题
y=-2asin(2x+π/6)+2a+b, π/6≤2x+π/6≤7π/6,
∴ -1/2≤sin(2x+π/6)≤1.
(1) 若a0, ∴ a≤-2asin(2x+π/6)≤-2a,
∴ 3a+b≤y≤b, 3a+b=-5,b=1, ∴ a=-2,b=1.
(2) 若a≥0,则-2a≤0, ∴ -2a≤-2asin(2x+π/6)≤a,
∴ b≤y≤3a+b, 3a+b=1,b=-5, ∴ a=2,b=-5.
错了
y=-2asin(2x+π/6)+2a+b, π/6≤2x+π/6≤7π/6,
∴ -1/2≤sin(2x+π/6)≤1.
(1) 若a0, ∴ a≤-2asin(2x+π/6)≤-2a,
∴ 3a+b≤y≤b, 3a+b=-5,b=1, ∴ a=-2,b=1.
(2) 若a≥0,则-2a≤0, ∴ -2a≤-2asin(2x+π/6)≤a,
∴ b≤y≤3a+b, 3a+b=1,b=-5, ∴ a=2,b=-5.
错了