case 1 : A-1\[\geq \] 0
=> A \[\geq \] 1
hence valid input for A is any real number greater than or equal to 1.
Case 2: 2 - X >0
=> X < 2.
So valid input for x is any real number less than 2.
Case 3 : B+5 \[\geq \] 0 & 2-B > 0
=> B \[\geq \] -5 and B < 2
=> -5 \[\geq \] B < 2.
So Valid input of B is any real no from -5 to 2 .excluding 2
