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Basic Mathematics – I




                    Notes          2.          exists.

                                   3.          = f(c).


                                   8.1 Continuity at a Point


                                          Example: Show that the function         is continuous at x = –3.

                                   1.                    =        f(c) is defined.



                                                         =



                                                         =               limit of a quotient



                                   2.                  limit of a root    exists.











                                   Therefore,           and f is continuous at x = –3.


                                   8.1.1 Continuity of Special Functions


                                       Every polynomial function is continuous at every real number.
                                       Every rational function is continuous at every real number in its domain.
                                       Every exponential function is continuous at every real number.
                                       Every logarithmic function is continuous at every positive real number.
                                       f(x) = sin x and g(x) = cos x are continuous at every real number.

                                       h(x) = tan x is continuous at every real number in its domain.

                                   8.1.2 Continuity from the Left and Right

                                       A function f is continuous from the right at x = a provided that
                                       A function f is continuous from the right at x = b provided that











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