|x+1|+|x+15|=2-12
|x+1|+|x+15|=-10
Vì |x+1|+|x+15| >= 0 mà -10<0
=> x vô nghiệm
|x+1| + 12 + |x+15| = 2
|x+1| + |x+15| = 2 - 12
|x+1| + |x+15| = - 10
Mà |x+1| + |x+15| \(\ge\) 0 > -10
\(\Rightarrow\) x \(\in\varnothing\)
\(\left|x+1\right|+12+\left|x+15\right|=2\\ \Leftrightarrow\left|x+1\right|+\left|x+15\right|=-10\\ \left|x+1\right|+\left|x+15\right|>0\\ \Rightarrow x\in\varnothing\)
|x+1| + 12 + |x+15| = 2
|x+1| + |x+15| = 2 - 12
|x+1| + |x+15| = - 10
Mà |x+1| + |x+15| ≥≥ 0 > -10
⇒⇒ x ∈∅