.

##### Continuity and Differentiability – Notes

**Continuity of a Function**

A function (x) is continuous at x = c, if (x) is defined at x = c and (x) =n (c).

If is not continuous at x = c, then we say is discontinuous at c, and c is called a point of discontinuity of .

A real function is said to be continuous, if it is continuous at every point in the domain .

**Concept of Infinity**

+ is a number larger than any given real number.

– is a number smaller than any given real number.