Given exp. f(x) = ax2 + bx + c ∴ When x = 0, a.0 + b.0 + c = 4 ⇒ c = 4. The remainders when f(x) is divided by (x + 1) and (x + 2) respectively are f(–1) and f(–2). ∴ f(–1) = a.(–1)2 + b.(–1) + c = 4 ⇒ a – b + c = 4 ⇒ a – b + 4 = 4 ⇒ a – b = 0 ...(i) f(–2) = a.(–2)2 + b(–2) + c = 6 ⇒ 4a – 2b + 4 = 6 ⇒ 4a – 2b = 2 ...(ii) Solving (i) and (ii) simultaneously we get, a = 1, b = 1.