Find the range of xxx satisfying ∣x+1∣+∣x−3∣=4|x+1| + |x-3| = 4∣x+1∣+∣x−3∣=4.
x=1x = 1x=1
x∈[−1,3]x \in [-1, 3]x∈[−1,3]
x∈[1,3]x \in [1, 3]x∈[1,3]
x∈(−1,3)x \in (-1, 3)x∈(−1,3)