\({9}\) is a square number. \(3 \times 3 = 9\) \(3 \times 3\) can also be written as \(3^2\). This is pronounced "\({3}\) squared". \({8}\) is a cube number. The ...

Then there was root-mean-square (RMS) voltage. For those nice sine waves, you took the peak voltage and divided by the square root of two, 1.414 or so. You know that kid in the front of the class?

Some quadratics cannot be factorised. An alternative method to solve a quadratic equation is to complete the square. To solve an equation of the form \(x^2 + bx + c = 0\) consider the expression ...