Which function is a quadratic function? a(x) = –2x3 + 2x – 6 b(x) = 5x3 + 8x2 + 3 c(x) = –8x2 + 3x – 5 d(x) = 6x4 + 2x – 3

The correct answer is: [C]:  " c(x) = –8x² + 3x – 5 " .

  The quadratic function takes the form of:

  " f(x) =  ax²  + bx + c " .

Answer choice:  [C]:  " c(x) = –8x² + 3x – 5 "  ;

  is the only answer choice provided that takes that form of the quadratic function:

  " f(x) =  ax²  + bx + c " :

in which:  " a = -8 " ; " b = 3 " ;  " c = -5 " .