Mathematics

Mathematics

Problem

For the polynomial p(x)=x3+ax2+bx+6p(x)=x^{3}+ax^{2}+bx+6, it is known that x=1x=1 is a factor and the remainder when p(x)p(x) is divided by x−2x-2 is 1010. Which ordered pair (a,b)(a,b) satisfies these conditions? a) (0,−7)(0,-7) b) (−5,−2)(-5,-2) c) (5,−12)(5,-12) d) (8,−15)(8,-15)
Intuitive explanation

The key is to translate the two given conditions into equations using the Factor Theorem and Remainder Theorem. Since x=1x=1 is a factor, p(1)=0p(1)=0; since dividing by x−2x-2 leaves remainder 1010, we have p(2)=10p(2)=10. These two equations in aa and bb are all you need to solve the system and find the unique pair.

Intuitive explanation

The key is to translate the two given conditions into equations using the Factor Theorem and Remainder Theorem. Since x=1x=1 is a factor, p(1)=0p(1)=0; since dividing by x−2x-2 leaves remainder 1010, we have p(2)=10p(2)=10. These two equations in aa and bb are all you need to solve the system and find the unique pair.

Browse the problem library