1. Is a = 0?
(1) a = a^2
(2) a = a^3 - a^2
2. Is ab < a?
(1) a = 0
(2) b = 0
plz solve then after I put oa
(1) a = a^2
(2) a = a^3 - a^2
2. Is ab < a?
(1) a = 0
(2) b = 0
plz solve then after I put oa
1) a=0???
a) a=a^2. a=0,1 Insufficient
b) a = a^3 - a^2 -> a(a^2-a-1)=0. a^2-a-1 is quadratic with discriminant >0, thus it has two roots (irrational) Thus not sufficient.
a&b) a=1 doesn't satisfy b. so only option left is a=0. Sufficient
IMO C
