How to plot quadratic functions, e.g. F(x)= x^2 + 2x +1
What we require to plot this graph are the following: the general shape of the graph, the intercepts with the x and y axes and the maximum point/minimum point. All functions with x2 as the highest order are a parabolic shape (sometimes referred to as a 'happy' or 'sad face'). The direction of this parabola depends if there is a negative sign in front of the term with x2. If it is negative, the parabola is a 'sad face' and if positive, it is a 'happy face'. In this case it is an upwards parabola (happy face) since x2 is positive. To find the intercepts with the x-axis, factorize the equation and set it equal to zero, and solve for x. To find the y-intercept, set x=0 and see what value of the function you get (e.g. F(x)= (0)2 +2(0) + 1 = 1 so the y intercept is 1). Thus draw the curve.
