Below is the graph of a quadratic function, showing where the function is increasing and decreasing. If we draw in the tangents to the curve, you will notice that if the gradient of the tangent is ...

Roula Khalaf, Editor of the FT, selects her favourite stories in this weekly newsletter. Nicholas and Timothy Green, nephews of former Carlton Communications chairman Michael Green, have found a ...

Theorem. Let $V$ be a complex analytic variety irreducible at a point $p \in V$. Given any integer $l$, there exists an analytic curve $C_l$ on $V$ passing through $p ...

When a relationship between two variables is defined by a curve it means that the gradient, or rate of change, is always varying. An average speed for a journey can be found from a distance-time graph ...