If a = {x is greater than or equal to - 3 and less than 1} B = {x is greater than or equal to A-1 and less than or equal to a} and the intersection of a and B is not an empty set, then the value range of a

If a = {x is greater than or equal to - 3 and less than 1} B = {x is greater than or equal to A-1 and less than or equal to a} and the intersection of a and B is not an empty set, then the value range of a

-3