Question

If the polynomials p(x)=2x³ +bx² +3x-5 and q(x)= x³+x² -4x-b leave the same remainder, when divided by x-2, prove that b = -13/5.​

Answer 1

Explanation:

Lets first find the remainder when p(x) is divided by x-2

p(2)=2(2)³+b(2)²+3(2)-5

p(2)=16+4b+6-5

p(2)=4b+17

Now let's find the remainder when q(x) is divided by x-2

q(2)=(2)³+(2)²-4(2)-b

q(2)=8+4-8-b

q(2)=4-b

Now let's equate both of them

4b+17=4-b

4b+b=4-17

5b=-13

b=-13/5 as required