If a function
has a positive average rate of change on the interval
.
Formula for the average rate of change from
to
is
.
Slope of a line could be interpreted as the average rate of change.
\ \Consider the two functions that have positive average rate of change on the interval
.
Graph of
: Graph of
:
Observe the above two graphs:
\The two example graphs satisfy
, but the function
is not increasing on
.
And the function
in increasing on
.
Therefore, the function
has a positive average rate of change on the interval
, is not necessary increasing on
.
Not necessarily. It just means
.