it's quite obvious that that's an assumption that it must be implicit and that you should know.

well then, by a well known property your inequality equals so you have to solve each one.

i'll help ya with the first one:

the numerator is a perfect square, but it has a critical point at but we don't actually want that, since that'd turn the numerator zero and the inequality won't be satisfied, so to solve the previous inequality we just require that but since we've stated that the first solution set is

apply the same procedure for the second inequality, that'd yield a second solution set, which you need to intersect with the first one to get the full solution set.