Completing the square means writing the unknown terms of a quadratic in a square bracket Example because Application To find the maximum or minimum value of this function. has a minimum value when x = – 3 Minimum value of is – 2 Minimum point on the curve is (– 3 , – 2)

Example To sketch the graph of line of symmetry y x has a minimum value when x = 1 5 Minimum point is (1, 3) (1, 3) Intercept on the y axis is 5 x = 1

(Note you can find the intercepts on the x axis by solving ) Example To sketch the graph of y x (–2, 7) x = –2 has a maximum value when x = – 2 3 Maximum point is (–2, 7) Intercept on the y axis is 3 (Note you can find the intercepts on the x axis by solving )