What information does the first derivative tell you?

1 Answer
Mar 8, 2015

The first derivative of a function y=f(x) tells you how your function changes when you change x or, if you consider the graph of your function, the inclination of the curve representing it:
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In the example, at P, for each change of 1 unit in x, y changes of 4.

If in P the function had an inclination downwards the derivative would have been negative.
If in P the function had minimum or maximum the derivative would have been zero

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Summarizing, derivative tells you how a variable quatity changes.

Hope it helps