Remainder theorem and factorization of polynomials
5 likes4,293 views
The remainder theorem states that the remainder of dividing a polynomial P(x) by (x-a) is equal to P(a). Some examples of using the remainder theorem to find the remainder of polynomial divisions are worked out. The document also discusses that a number a is a root of a polynomial P(x) if P(a) equals 0. If a is a root, then (x-a) is a factor of the polynomial P(x). Examples of finding roots and corresponding factors of polynomials are provided.
1 of 13
Downloaded 66 times
Remainder theorem and factorization of polynomials
- 1. Remainder theorem and factorization of polynomials by Suso
- 2. Remainder theorem The remainder of the division of a polynomial P(x) by (x-a) is P(a). For example, if P(x)=3x3-2x+5, the remainder of the division of P(x) by (x-2) is equal to P(2)=3·23-2·2+5=25
- 3. Exercise What is the remainder of the division of P(x)=5x4-3x3+3x2+x-2 by (x-3)? Check your result using the synthetic division
- 4. Exercise What is the remainder of the division of P(x)=-4x3-4x2+9x by (x+2)? Check your result using the synthetic division
- 5. Exercise Is the division (8x3-4x+12)(x+1) exact?
- 6. Exercise Is the division (2x5+3x4+2x3-4x2+12)(x-2) exact?
- 7. Exercise What is the remainder of the division (2x35+3x24+12)(x+1)?
- 8. Root of a polynomial A number a is called a root (or a zero) of a polynomial P(x) if P(a)=0.
- 9. Root of a polynomial. Example Let´s consider the polynomial P(x)=x3-3x2-2x+6. If we plug in x=3 into the polynomial, we get: P(3)=33-3·32-2·3+6 ⇒ P(3)=0 Then, 3 is a root of the polynomial P(x)
- 10. Root of a polynomial. Example Note that x-3 is a factor of the polynomial P(x)=x3-3x2-2x+6. (the division is exact)
- 11. Roots and factors of a polynomial a is a root of a polynomial P(x) ↕ P(a)=0 ↕ (x-a) is a factor of P(x)
- 12. Exercise Is− 2 a root of P(x)=x3-3x2-2x+6?
- 13. Exercise In that case, ...............is a factor of P(x).