Finding a function to fit a curve

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I have coordinates of four points on a curve and want to find a function that will draw the curve.

The points are [0,0] [120,280] [240,2800] [360,28000]

It looks like an exponential curve in that 120 is 1/3 of 360 and 280 is 2.8 * 100, 240 is 2/3 of 360 and 2800 is 2.8 * 1000, 360 is 3/3 of 360 and 28000 is 2.8 * 10000

It looks like it should be a simple function. I tried the function finder on ZunZun but it produced hideously complicated functions that didn't output exact results.

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The point $(0,0)$ is ruining your exponential. The other points fit $y=28\cdot 10^{x/120}$ perfectly. If the first point were $(0,28)$ it would fit as well. If you got your data off a graph, can you tell the difference between the two points?