Vinh Tuong Education Departure
Vinh Tuong Secondary School

1
2
3
4 5 6

Unit 8: Period 20
th

PRACTICE PROBLEMS ON POLYNOMIALS
We have:
n
3
- 8n
2
+ 20n - 13 = (n - 1)(n
2
- 7n +13)
Because n
3
- 8n
2
+ 20n - 13 are prime numbers
2
1 1
7 13 is
n
SO

1 1
If
7 13 is 2
n
n n a prime n
− =



− + ∴ =


2
1 is
If 3 or 4
7 13 1
n a prime
n n
n n

−

∴ = =

− + =


PRACTICE PROBLEMS ON POLYNOMIALS
Therefore n = 2; n = 3; n = 4 then n
3