# 11X1 T15 05 polynomial results (2011)

Post on 08-Jul-2015

836 views

TRANSCRIPT

- 1. Polynomial Results

2. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x). 3. Polynomial Results 1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x). 4. Polynomial Results 1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 1043 2 0 5. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 6. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 1, 2 are zeros of P ( x) and x 1 x 2 is a factor 7. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 1, 2 are zeros of P ( x) and x 1 x 2 is a factorP( x) x 4 x 3 3 x 2 5 x 10 8. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 1, 2 are zeros of P ( x) and x 1 x 2 is a factorP( x) x 4 x 3 3 x 2 5 x 10 x2 x 2 9. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 1, 2 are zeros of P ( x) and x 1 x 2 is a factorP( x) x 4 x 3 3 x 2 5 x 10 x2 x 2 x2 10. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 1, 2 are zeros of P ( x) and x 1 x 2 is a factorP( x) x 4 x 3 3 x 2 5 x 10 x2 x 2 x2 5 11. Polynomial Results1. If P(x) has k distinct real zeros, a1 , a2 , a3 ,, ak , then; x a1 x a2 x a3 x ak is a factor of P(x).e.g. Show that 1 and 2 are zeros of P( x) x 4 x 3 3 x 2 5 x 10 and hence factorise P(x).P 1 1 1 3 1 5 1 10432 0P 2 2 2 3 2 5 2 10 4 320 1, 2 are zeros of P ( x) and x 1 x 2 is a factorP( x) x 4 x 3 3 x 2 5 x 10 x2 x 2 x25 x 1 x 2 x 2 5 12. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 13. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct real zeros 14. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct realzerose.g. The polynomial P(x) has a double zero at 7 and a single zero at 2. Write down; a) a possible polynomial 15. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct realzerose.g. The polynomial P(x) has a double zero at 7 and a single zero at 2. Write down; a) a possible polynomial P( x) x 2 x 7 2 16. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct realzerose.g. The polynomial P(x) has a double zero at 7 and a single zero at 2. Write down; a) a possible polynomialP( x) x 2 x 7 Q( x)2where - Q(x) is a polynomial and does not have a zero at 2 or 7 17. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct realzerose.g. The polynomial P(x) has a double zero at 7 and a single zero at 2. Write down; a) a possible polynomialP( x) k x 2 x 7 Q( x)2where - Q(x) is a polynomial and does not have a zero at 2 or 7- k is a real number 18. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct realzerose.g. The polynomial P(x) has a double zero at 7 and a single zero at 2. Write down; a) a possible polynomialP( x) k x 2 x 7 Q( x)2where - Q(x) is a polynomial and does not have a zero at 2 or 7- k is a real number b) a monic polynomial of degree 3. 19. 2. If P(x) has degree n and has n distinct real zeros, a1 , a2 , a3 ,, an , then P x x a1 x a2 x a3 x an 3. A polynomial of degree n cannot have more than n distinct realzerose.g. The polynomial P(x) has a double zero at 7 and a single zero at 2. Write down; a) a possible polynomialP( x) k x 2 x 7 Q( x)2where - Q(x) is a polynomial and does not have a zero at 2 or 7- k is a real number b) a monic polynomial of degree 3. P( x) x 2 x 7 2 20. c) A monic polynomial of degree 4 21. c) A monic polynomial of degree 4 P( x) x 2 x 7 2 22. c) A monic polynomial of degree 4 P( x) x 2 x 7 x a 2 where a 2 or 7d) a polynomial of degree 5. 23. c) A monic polynomial of degree 4 P( x) x 2 x 7 x a 2 where a 2 or 7d) a polynomial of degree 5.P( x) x 2 x 7 2 24. c) A monic polynomial of degree 4 P( x) x 2 x 7 x a 2 where a 2 or 7d) a polynomial of degree 5.P( x) x 2 x 7 Q( x) 2 where - Q(x) is a polynomial of degree 2, and does not have a zero at 2 or 7 25. c) A monic polynomial of degree 4 P( x) x 2 x 7 x a 2 where a 2 or 7d) a polynomial of degree 5.P( x) k x 2 x 7 Q( x) 2 where - Q(x) is a polynomial of degree 2, and does not have a zero at 2 or 7 - k is a real number 26. c) A monic polynomial of degree 4 P( x) x 2 x 7 x a 2 where a 2 or 7d) a polynomial of degree 5.P( x) k x 2 x 7 Q( x) 2 where - Q(x) is a polynomial of degree 2, and does not have a zero at 2 or 7 - k is a real number4. If P(x) has degree n and has more than n real zeros, then P(x) is the zero polynomial. i.e. P(x) = 0 for all values of x 27. Exercise 4E; 1, 3bd, 4a, 5b, 6a, 8, 12ad