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disregardthat
Feb15-07, 03:11 PM
Is is possible to calculate the growth-rate to a tangent in a graph? (like f(x)=x^2

I only know how to draw the line on the graph, but how do you calculate it if you know the point where you must draw the tangent?

For example: find the tangent of the point x=2 on a graph f(x)=x^2

How do you find the rate of growth?

mathman
Feb15-07, 03:28 PM
This is one of the first things you learn about in elementary calculus. The tangent (slope) at a point on a curve is given by the first derivative at that point.

disregardthat
Feb15-07, 03:38 PM
I have only had one class in calculus, and we learned the average rate of change. Then we got two points in a graph, and calculated the average slope. I know what a tangent of a graph is, and I have managed to sort out the somewhat accurate answer with only drawing the line, but I don't know how to calculate it.

And what is a derivative? Is a derivative the average slope for two points of the x-axis on a graph?

Werg22
Feb15-07, 04:24 PM
Your are talking about the whole limiting process that the derivative is. You will eventually learn how to calculate the slope of the tangent with analytical methods if you follow a calculus course.

disregardthat
Feb15-07, 11:23 PM
Man!

:tongue2:

anantchowdhary
Feb16-07, 12:08 AM
The slope here for x=2 is 4.If you take the derivative of f(x)=x^2,you get dy/dx=2x

now substitute the value of x and you get the slope!