Home › SPM Add Maths › Quadratic Functions › (A) General Form of Quadratic Function

(A) General Form of Quadratic Function

Posted on by

3.1 General Form of Quadratic Function
General form of a quadratic function is f ( x ) = a x 2 + b x + c where a, b, and c are constants and a ≠ 0, and x as a variable.

Example:
Determine which of the following is a quadratic function.
  1. f ( x ) = ( 5 x − 3 ) ( 3 x + 8 )
  2. f ( x ) = 2 ( 3 x + 8 )
  3. f ( x ) = 5 2 x 2
Answer:
(a)
  f ( x ) = ( 5 x − 3 ) ( 3 x + 8 ) f ( x ) = 15 x 2 + 40 x − 9 x − 24 f ( x ) = 15 x 2 + 31 x − 24
Quadratic function

(b)
f ( x ) = 2 ( 3 x + 8 ) f ( x ) = 6 x + 16
Not quadratic function


(c) Not quadratic function