<math>\frac{d}{dx} \left(\frac{u}{v}\right) = \frac{v \left(\frac{du}{dx}\right) - u \left(\frac{dv}{dx}\right)}{v^2}</math>
<math>\frac{d}{dx} \left(\frac{u}{v}\right) = \frac{v \left(\frac{du}{dx}\right) - u \left(\frac{dv}{dx}\right)}{v^2}</math>
+
+
It is easily remembered by the rhyme "Low 'D' High minus High 'D' Low, draw the line, and square below" (the denominator times the derivative of the numerator minus the numerator times the derivative of the denominator all over the denominator squared).