 # Precalculus Section 1.7 Define and graph quadratic functions

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Precalculus Section 1.7 Define and graph quadratic functions
Any function that can be written in the form: y = ax2 +bx + c is called a quadratic function. It’s graph is called a parabola. Consider the graphs of the quadratic functions: y = x2 y = 2x2 y = -2x2 y = x2 – x – 6

The graph of y = ax2 +bx + c has an axis of symmetry of x = -b/2a, roots which are the solution of ax2 +bx + c = 0, a y-intercept of c, and the x value of the vertex is x = -b/2a. If a>0 the parabola opens up, if a<0 the parabola opens down. Find the x and y intercepts, axis of symmetry, the vertex, and sketch the graph of y = -x2 + 4x - 3

Graph f(x) = 2x2 + 5x - 12

Vertex form of a quadratic function y = a(x-h)2 + k
(h,k) is the vertex, x=h is the equation of the axis of symmetry. Find the vertex, intercepts, axis, and sketch the graph of y = -1(x+2)2 + 3

Graph f(x) = 2(x-4)2 - 5

Find the equation of the parabola with a vertex of (4,8) and passing through the point (2,6).

Assignment Page 41 Problems 2,4,7,12,14,16,18,21,22,29,32 38 e.c.