## Formulae and Identities

**Trigonometry**

Ifis to be written in the formthenand Ifis to be written in the formthen use and

**Calculus and Algebra**

Ifhas a turning point (also called a stationary or maximum or minimum) atthenatIfatthenhas a minimum atIfat thenhas a maximum atIf then no conclusion may be drawn from this test. The nature of the stationary point may be deduced by sketching the curve in the vicinity of the point.

Ifthen the completed square form foris

The minimum value of y can then be read off. This minimum value isand this minimum value occurs at

**Logarithms**