Question

Use the remainder theorem for x^3+8x^2+11x-20 by x+4. Use the remainder theorem for x^3+8x^2+11x-20 by x-5.

Answer 1

the remainder for both expressions is zero

Explanation:

1. (x+4)=0
2. x=-4
3. x³+8x²+11x-20, where x=-4
4. (-4)³+8(-4)²+11(-4)-20
5. -64+128-44-20
6. 0, Hence it has no remainder

• (x+5)=0

1. x=-5
2. x³+8x²+11x-20, where x=-5
3. (-5)³+8(-5)²+11(-5)-20
4. -125+200-55-20
5. 0, hence it has no remainder