Question
Question: Solve the following system of inequalities: ∣2x−3∣≤11 and ∣ x − 2 ∣ ≥ 3 ∣x−2∣≥3...
Solve the following system of inequalities:
∣2x−3∣≤11 and ∣ x − 2 ∣ ≥ 3 ∣x−2∣≥3
x ∈ [-4, -1] ∪ [5, 7]
Solution
To solve the given system of inequalities, we will solve each inequality separately and then find the intersection of their solution sets.
Inequality 1: ∣2x−3∣≤11
This absolute value inequality can be rewritten as a compound inequality: −11≤2x−3≤11
Add 3 to all parts of the inequality: −11+3≤2x≤11+3 −8≤2x≤14
Divide all parts by 2: 2−8≤x≤214 −4≤x≤7 The solution set for the first inequality is x∈[−4,7]. Let's call this set S1.
Inequality 2: ∣x−2∣≥3
This absolute value inequality can be rewritten as two separate inequalities: x−2≥3ORx−2≤−3
Solve the first part: x−2≥3 x≥3+2 x≥5
Solve the second part: x−2≤−3 x≤−3+2 x≤−1
The solution set for the second inequality is x∈(−∞,−1]∪[5,∞). Let's call this set S2.
Finding the Intersection of the Solution Sets
We need to find the values of x that satisfy both inequalities, which means finding the intersection of S1 and S2: S1∩S2=[−4,7]∩((−∞,−1]∪[5,∞))
To find this intersection, we can consider the intersection of [−4,7] with each part of S2 and then take their union: ([−4,7]∩(−∞,−1])∪([−4,7]∩[5,∞))
-
Intersection of
[-4, 7]
and(-∞, -1]
: The numbers that are greater than or equal to -4 AND less than or equal to -1 are in the interval [−4,−1]. -
Intersection of
[-4, 7]
and[5, ∞)
: The numbers that are less than or equal to 7 AND greater than or equal to 5 are in the interval [5,7].
Combining these two resulting intervals with a union gives the final solution: [−4,−1]∪[5,7]
The solution represents all real numbers x such that x is between -4 and -1 (inclusive) or x is between 5 and 7 (inclusive).