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12 votes
Choose the expression that represents a quadratic expression.

O 6x4 - 5x3 + 3x2 -7x - 8
) 5x3 + 3x2 -7x - 8
O 2x2 + 3x - 1
. 3x - 1

2 Answers

10 votes

Answer:

2x2 + 3x - 1

Explanation:

User Biren
by
3.8k points
5 votes

Answer:

3) 2
x^(2) + 3x - 1

Explanation:

A quadratic expression is an expression involving a squared term

It can be written as y = a
x^(2) + bx + c, where a ≠ 0

// note that here b and c can be equal to 0

1) 6
x^(4) - 5
x^(3) + 3
x^(2) - 7x - 8 is simply incorrect because you can't write in the previously mentioned form. It is a quartic function, since the unknown variable x in forth degree. It can be written as y = a
x^(4) +b
x^(3) +c
x^(2) + dx + e, where a before
x^(4) ≠ 0

2) 5
x^(3) + 3
x^(2) - 7x - 8 is simply incorrect because you can't write in the previously mentioned form. It is a cubic function, since the unknown variable x in third degree.

3) 2
x^(2) + 3x - 1 is correct

4) 3x - 1 is incorrect because there is no squared term. You could also say that here a = 0 and write it as y = 0 *
x^(2) + 3x - 1. It is also called a linear function because if you'd draw a graph, it would be a line

User Edess Elder
by
3.5k points