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44 votes
44 votes
Write a polynomial of least degree with roots 2 and – 7

User Javier Heisecke
by
3.0k points

2 Answers

5 votes
5 votes

Answer:

y = x² + 5x - 14

Explanation:

Given roots x = a, x = b, then the corresponding factors are

(x - a) and (x - b) and the polynomial is the product of the factors

y = (x - a)(x - b)

Here the roots are x = 2 and x = - 7, then the factors are

(x - 2) and (x - (- 7)) = (x + 7), so

y = (x - 2)(x + 7) ← expand using FOIL

y = x² + 5x - 14

User Oleg Somov
by
2.7k points
7 votes
7 votes

Answer: x^2+5x-14

Step-by-step explanation:

2 and -7 are the roots of the polynomial then we have to write them as

x=2 ,x=-7

To convert these as factors, we have to write them as

( x-2) (x+7)

The product of those factors will give the polynomial. Because we have two factors, we will get a quadratic polynomial.

x^2+7x-2x-14

x^2+5x-14

Number of factors = Highest exponent of the polynomial

User Janet
by
3.3k points