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**Zooming in, but not through the origin**

This is continuing the analysis of the data the Excel file analysis1 V2, in the leaf The Data, 2 that we started to analyse in the previous page.

How about if we do not know it goes through the origin? We can then add points to the last column:

The values were chosen to make the slope as small or big as possible. The plot would now look like:

The slopes are 0.137 and 0.106. That gives us 0±0.2. The “*y*”-intercepts are 0.046 and –0.097, that gives us –0.03±0.08.

This will finally give us

*R*=(1.4±0.2)*L *–0.03±0.08

The difference between the two cases, the previous analysis and this one, is if you can assume it is a proportionality (goes through the origin) or not.

As you can see the result from this analysis is consistent with the result from the previous one, *R*=(1.41±0.05)*L.* The value zero is in the range –0.03±0.08, and 1.41±0.05 is within the range 1.4±0.2.

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