Answer
$a=\frac{1}{7}$ and $b=1$
Work Step by Step
We are given:
$|x+1|\leq 3$
$-3\leq x+1\leq 3$
We add 4:
$1\leq x+5\leq 7$
And take the reciprocal:
$1\geq\frac{1}{x+5}\geq\frac{1}{7}$
$\frac{1}{7}\leq\frac{1}{x+5}\leq 1$
Therefore:
$a=\frac{1}{7}$ and $b=1$