QUADRATIC FUNCTION
QUADRATIC FUNCTION

   It´s a polynomial function of second degree,
    whose graph is a curve called parabola.

                 f ( x) a x2 bx c
   Where a,b and c are constan, c is the interts,
    a≠0 , c is the y-intercept.
VERTEX FORM OF THE QUADRATIC FUNCTION

                          (y-k)=(x-h)2
 Where (h,k) are the coordinates of the vertex
                Simmetry axis
                                     The coordinate x of the
                                                                  b
                                     vertex (the h value) is x
                                                                 2a

                                      The coordinate y of the
                                      vertex (the k value) is f(h)



                      Vertex (h,k)
 The vertex can be a maximum value or a
  minimum value.
 The vertex is maximum if the parabola opens
  downwards a<0



    The vertex is minimum if the parabola opens
    upwards a>0
Solve:                                 f(x)= -x2+2x+8      a=-1     b=2
c=8

A) Find the roots(x intercepts)
B) Find the vertex
C) Find the y-intercept
D) Write the equation of the symmetry axis
E) Sketch the graph
                                      C) Find the y-intercept c=8
A) 0=-x2+2x+8
    0=-(x2-2x-8)                    D) Write the equation of the symmetry axis
    0=(x2-2x-8)                     x=1
0=(x-4)(x+2)
Roots are x=4, x=-2

B) Find the vertex(h,k)
h= -b/2 a = -(2)/2(-1) = 1
k= f(h)= -(1)2+2(1)+8 = 9
E) Sketch the graph
SOLVE F(X)= 3X2-9X-12

 A) Find the roots(x intercepts)
 B) Find the vertex
 C) Find the y-intercept
 D) Write the equation of the symmetry axis
 E) Sketch the graph
 f(x)= 3x2-9x-12
 f(x)= x2-4x+4
 f(x)= -16x2+256x
f(x)= 3x2-9x-12




    f(x)= x2-4x+4
f(x)= -16x2+256x
   Which of the following equations
    corresponds to the next graph?
    a) y   0.5( x 2)( x 4)
    b) y   0.1( x 6)( x 4)
    c) y    0.5( x 6)( x 2)
    d)y     0.1( x 6)( x 4)
   Match each equation with the corresponding
    graph

                     2
    a) y    0.5 x
                 2
    b) y   0.5 x
                    2
    c) y    0.2 x
    d)y     2.5 x 2
FIND ELEMENTS OF THE PARABOLA
a) y   0.5( x 2) 2   4
b) y   0.5( x 2) 2   4
c) y   0.5( x 2) 2   4
d)y    0.5( x 2) 2   4

Quadratic function

  • 1.
  • 2.
    QUADRATIC FUNCTION  It´s a polynomial function of second degree, whose graph is a curve called parabola. f ( x) a x2 bx c  Where a,b and c are constan, c is the interts, a≠0 , c is the y-intercept.
  • 3.
    VERTEX FORM OFTHE QUADRATIC FUNCTION  (y-k)=(x-h)2  Where (h,k) are the coordinates of the vertex Simmetry axis The coordinate x of the b vertex (the h value) is x 2a The coordinate y of the vertex (the k value) is f(h) Vertex (h,k)
  • 4.
     The vertexcan be a maximum value or a minimum value.  The vertex is maximum if the parabola opens downwards a<0 The vertex is minimum if the parabola opens upwards a>0
  • 5.
    Solve: f(x)= -x2+2x+8 a=-1 b=2 c=8 A) Find the roots(x intercepts) B) Find the vertex C) Find the y-intercept D) Write the equation of the symmetry axis E) Sketch the graph C) Find the y-intercept c=8 A) 0=-x2+2x+8 0=-(x2-2x-8) D) Write the equation of the symmetry axis 0=(x2-2x-8) x=1 0=(x-4)(x+2) Roots are x=4, x=-2 B) Find the vertex(h,k) h= -b/2 a = -(2)/2(-1) = 1 k= f(h)= -(1)2+2(1)+8 = 9
  • 6.
  • 7.
    SOLVE F(X)= 3X2-9X-12 A) Find the roots(x intercepts)  B) Find the vertex  C) Find the y-intercept  D) Write the equation of the symmetry axis  E) Sketch the graph  f(x)= 3x2-9x-12  f(x)= x2-4x+4  f(x)= -16x2+256x
  • 8.
    f(x)= 3x2-9x-12 f(x)= x2-4x+4
  • 9.
  • 10.
    Which of the following equations corresponds to the next graph? a) y 0.5( x 2)( x 4) b) y 0.1( x 6)( x 4) c) y 0.5( x 6)( x 2) d)y 0.1( x 6)( x 4)
  • 11.
    Match each equation with the corresponding graph 2 a) y 0.5 x 2 b) y 0.5 x 2 c) y 0.2 x d)y 2.5 x 2
  • 12.
    FIND ELEMENTS OFTHE PARABOLA
  • 13.
    a) y 0.5( x 2) 2 4 b) y 0.5( x 2) 2 4 c) y 0.5( x 2) 2 4 d)y 0.5( x 2) 2 4