Question

帮忙解题，谢谢。

Answer 1

A= { x|x^2-3x-10≤0}
={ x| (x-5)(x+2)≤0}
={ x| -2≤x≤5}
B= { x|m+1≤x≤ 2m-1}

B is subset of A
case 1: B=Φ
2m-1 < m+1
m< 2

case 2: B≠Φ , ie m≥2
B is subset of A
-2≤m+1 and 2m-1≤5
m≥-1 and m≤3
-1≤m≤3
solution for case 2: 2≤m≤3

B is subset of A
=>
case 1 or case 2
(m< 2) or 2≤m≤3
m≤3

Answer 2

x&#178;-3x-10≤0

(x+2)(x-5)≤0

-2≤x≤5

1. B=&#8709;
   

   m+1>2m-1

   2m-m<1+1

   m<2

2. -2≤m+1，且2m-1≤5

   m≥-3，且2m≤6

   m≤3

   -3≤m≤3

所以

m≤3

追问

谢谢。