Question

Formulate the quadratic function that contains the points (-1,2), (0,-1) and (2,5).

1.) f(x) = 2x^2 + x + 1
2.) f(x) = 2x^2 - x - 1
3.) f(x) = 2x^2 - x + 2
4.) f(x) = 2x^2 - x - 2

Answer 1

option 2

2x²- x - 1

Explanation:

We are given points: (-1,2), (0,-1) and (2,5)

Substitute each point one by one in the quadratic equation to check if the quadratic equation contains all points mention.

2) f(x) = 2x²- x - 1

Point(-1,2)

f(-1) = 2(-1)² -(-1) -1

2 = 2 + 1 - 1

2 = 2

Point(0,-1)

f(0) = 2(0)² -(0) -1

-1 = 0 - 0 -1

-1 = -1

Point(2,5)

f(2) = 2(2)² -(2) -1

5 = 8 - 2 -1

5 = 6 - 1

5 = 5