Question

Una función cuadrática es de la forma f(x)=ax^2+bx+c, donde a, b y c son número reales y a es diferente de cero. De acuerdo con este enunciado cual no es una función cuadrática. * f(x)=3x^2+12x+5 f(x)=x^2+x+1 f(x)=5x^2+8x f(x)=5x+3

Answer 1

option (4)

Explanation:

The general form of a quadratic function is given by :

`f (x) = ax^ 2 + bx + c`

Where a,b and c are real numbers and a is nonzero.

Option (1)

`f (x) = 3x^ 2 + 12x + 5`

It is a quadratic function. Here, a = 3, b = 12 and c = 5

Option (2),

`f (x) = x^ 2 + x + 1`

It is a quadratic function where a = 1, b = 1 and c =1

Option (3),

`f(x)=5x^ 2 + 8x`

It can also be written as :

`f(x)=5x^ 2 + 8x+0`

It is a quadratic function where a = 5, b = 8 and c = 0

Option (4),

It can also be written as :

f(x) = 5x + 3

It is a linear function. It is not a quadratic function.

Hence, option (4) is the correct option. It is not a quadratic function.