For any numbers a and b, a · b = a + b - ab. If a · b = 0, which of the following CANNOT be a value of b?
(A) 2
(B) 1
(C) 0
(D) -1
(E) -3/2
(A) 2
(B) 1
(C) 0
(D) -1
(E) -3/2
For any numbers a and b, a · b = a + b - ab. If a · b = 0, which of the following CANNOT be a value of b?
(A) 2, If b = 2 then a+b-ab=0 => a+2-2a=0 => a = 2. So b can be 2
(B) 1, If b = 1 then a+1-a=0 => 1 = 0. Impossible! So b cannot be 1
(C) 0
(D) -1
(E) -3/2
Answer B
