Question

巡游月球_CruiseMoon

求解謝謝^_^

3.設x>0,求
(x+2)(x+10)
x+1
之最小值爲
此時z=

Answer 1

✨ 最佳解答 ✨

我就是我

(x+2)(x+10)/(x+1)
=(x²+12x+20)/(x+1) 除法除下去
=(x+11) + 9/(x+1)
=10+ (x+1)+9/(x+1) 算幾
=10+6
=16
此時x+1=9/(x+1)，x=2