# Applications of Differentiation : Math Review

math tutorials > applications of differentiation

## Derivatives & Straight Line Graphs

The derivative *f'(x)* is the **gradient** of the **tangent** of
the graph of *f* at the point *x*. In a **straight
line** graph the derivative is the gradient of the graph.

The **normal** to a curve at any point is the line perpendicular
to the tangent at that point.

The gradient of two perpendicular lines has a product of –1.

## Differentiation math problems for you to try.

*Solutions: * 1) -1 2) -1 3) -2 4) 2