来自龙朝晖的问题
若实数a,b满足ab-4a-b+1=0(a>1),则(a+1)(b+2)的最小值为______.
若实数a,b满足ab-4a-b+1=0(a>1),则(a+1)(b+2)的最小值为______.


若实数a,b满足ab-4a-b+1=0(a>1),则(a+1)(b+2)的最小值为______.
若实数a,b满足ab-4a-b+1=0(a>1),则(a+1)(b+2)的最小值为______.
∵ab-4a-b+1═0
∴b=4a−1a−1