Q1. Solve the inequalities and show the solution sets on the real line.
a) −2𝑥2−𝑥+3≥0
b) 13𝑥+23<56𝑥−1
c) 3𝑥−3≥𝑥−5
d) 4<𝑥2<9
e) √(𝑥−1)2 <√4
a)
-2x²-x+3≥0
=> 2x²+x-3≤0
=> 2x²+3x-2x-3≤0
=> (2x+3)(x-1)≤0
=> (x+1.5)(x-1)≤0
So x "\\isin" [-1.5, 1]
b)
13x+23 < 56x-1
=> 13x-56x < -1-23
=> -43x < -24
=> x > 24/43
So x "\\isin ( \\frac{24}{43} , \u221e)"
c)
3x-3≥x-5
=> 3x - x ≥ -5+3
=> 2x ≥ -2
=> x ≥ -1
So x "\\isin [-1, \u221e)"
d)
4 < x² < 9
=> x² > 4 and x² <9
=> {x <-2 or x > 2 } and -3<x<3
=> {-3<x<-2} or {2<x<3}
So x "\\isin (-3,-2)\\bigcup(2,3)"
e)
"\\sqrt{(x-1)\u00b2} < \\sqrt{4}"
=> | x - 1 | < 2
=> -2 < x - 1 < 2
=> -2 +1 < x < 2+1
=> -1 < x < 3
So x "\\isin (-1, 3)"
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