QUAD

• Quadratic function


  A second degree polynomial function of the form f(x) = ax^2 + bx + c
• How to know if a function is quadratic

  1. By equation

  2. By table of values

  3. By graph
• Quadratic function graph

  • Parabola shape
  • Can be upwards or downwards = the 2 func of parabola
  • Has a vertex (lowest or highest point)
• Vertex


  The first point of the graph

  Represented by y = a(x-h)^2 + k

  Lowest point of an upward parabola

  Highest point of a downward parabola

  Can be solved by -b/2a
• Parabola opening

  • Upwards if a > 0

  Downwards if a < 0
• Parabola axis of symmetry


  • x = h
• Parabola y-intercept

  • Only for upward parabolas

  Set x = 0 to find y-intercept (0, y)
• Parabola x-intercepts

  • Set y = 0 to find x-intercepts (x, 0)
• Quad formula

  -b +/- (/b2 - 4ac) / (2a)

  simplifying radicals:

  dont simplify if prime
• Quadratic eq can be solved through

  standard formula

  factoring

  completing squares

  quadratic formula
• 2nd difference of table values if same for all that is a quadratic func.
• H= -b/2a