Va rog ajutati.ma cu cateva exerciti ..multumesc anticipat <3

1.. 3(2x+1) - 5 (1-2x) mai mic sau egal (1-3x) ori ( -6) +18

2.. 5x-7-(-2) (x+4) mai mic sau egal 2 [3(x-1) -4 (x-2)]

3. 5x+1 supra 6 +3x-1 supra 5 < (mai mic) 9x+1 supra 15 -1-x supra 3 -8supra 30

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Răspunsuri

2014-05-05T18:36:34+03:00
1)⇒ 6x+3-5+10x≤-6+18x+18
16x--2≤18x+24
16x-18x≤24+2
-2x≤26                  ·(-1)
x≥26/2
x≥13
x∈[1,+α)
2) ⇒5x-7+2x+8≤2(3x-3-4x+8)
7x+1≤2(-x+5)
7x+1≤-2x+10
7x+2x≤10-1
9x≤9
x≤9/9
x≤1
x∈(-α,1]
3)⇒(25x+5+18x-6)/30≤(18x+2-10+10x-8)/30
43x-1≤28x+4
43x-28x≤4+1
15x≤5
x≤5/15
x≤1/3
x∈(-α,1/3]
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