Question

if ax^3+bx^2+x-6 has x+2 as a factor and leaves a remainder 4 when divided by x-2 find the value of a and b

Answer 1

F(x) = ax3 + bx2 + x – 6 F(- 2) = -8a + 4b – 2 – 6 = -8a + 4b – 8 = 0  So, 2a – b + 2 = 0 ……(i) F(2) = 8a + 4b + 2 – 6 = 8a + 4b – 4 = 4  So, 2a + b – 2 = 0 ……..(ii)   From (i) and (ii), we get        a = 0 , b = 2,