Question

数学，解不等式

Answer 1

⑵2x²-x-1≥0,(2x+1)(x-1)≥0,
x≤-0.5或x≥1

⑶(x-1)²≥0,
x取所有实数R

⑷（x+1）²+3＜0,
x无实数解

⑸（x-2）（x+3）≤0且x+3≠0,
-3＜x≤2

⑹2x²-3x-5≥0,(2x-5)(x+1)≥0,
x≤-1或x≥2.5

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追答

第二题在最上面，自己要分清对错(x-2)(3-x)=-x²+5x-6

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sorry

Answer 2

(3)
x^2-2x+1≥0
(x-1)^2 ≥ 0
-∞<x<+∞

(4)
x^2+2x+4<0
(x+1)^2 +3 <0
没有实数解

(5)
(x-2)/(x+3)≤0
-3<x≤2

(6)
√(2x^2-3x-5)≥0
2x^2-3x-5 ≥0
(2x-5)(x+1)≥0
x≥5/2 or x≤-1

追问

好了就采纳，谢谢

追答

(x-2)(3-x)≤ x(x+4) -7
-x^2+6x-6 ≤ x^2+4x -7
2x^2-2x-1 ≥0
2(x - 1/2)^2≥ 3/2
(x - 1/2)^2≥ 3/4
x-1/2 ≥ √3/2 or x-1/2 ≤ -√3/2
x ≥ (1+√3)/2 or x ≤ (1-√3)/2