A calculus of the absurd
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4.3 Quadratics
4.3.1 Introduction
A quadratic is an equation in the form
\(\seteqnumber{0}{4.}{7}\)\begin{equation} y = ax^2 + bx + c \end{equation}
One example quadratic is
\(\seteqnumber{0}{4.}{8}\)\begin{equation} y = x^2 \end{equation}
Note that “\(\cdot \)” is the same as “\(\times \)”.
We can find the value of this at different points - for example, when \(x=1\), then \(y=1\), when \(x=4\) then \(y=4\cdot 4=16\) and when \(x=3.123\) then \(y=3.123\cdot 3.123=9.753129\).
We can also plot them on a graph. For example, the quadratic \(y=x^2\) looks like
