How to convert trendline with E into Excel formula?

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How do I write this formula in an Excel cell? y = 4E-11x3 - 3E-07x2 + 0.001x

7 Replies

@fradella100 

Perhaps you mean

=4E-11*A1^3 - 3E-07*A1^2 + 0.001*A1
I understand how to raise cell A1 to the exponent of 3 "A1^3"
What do I do with the 4E?

@fradella100 

That's scientific notation for the number. 4E-11 is the same as 0.00000000004

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@Sergei Baklan 

 

Using the E as scientific notation does not work.  

 

Here is my data

CD14 Concentration (pg/mL)Average
20001.016
10000.706
5000.440
2500.255
1250.140
62.50.101
00.000

y = 1E-10x3 - 6E-07x2 + 0.0012x

 

How can I write the slope formula so that I get reasonable values when solving unknows ie x?

@fradella100 

Formula gives not exact but close to your data result

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Please note, if you enter the formula with scientific notation Excel automatically converts such numbers to "number" format where possible.

For example, if you type

image.png

 after you hit Enter same formula will be shown as

image.png

(in A1 is number 2).

Please let me rephrase my question. When I make a scatter plot graph with the above data, add a trend line I get the slope equation of "y = 1E-10x3 - 6E-07x2 + 0.0012x". How do I write this formula in a cell to solve for unknow x values? The response above has 0.8 and then the formula but does not give a result that should be 2,000.

@fradella100 

Sorry, I'm missed - where is X and where is Y in your sample? Trendline formula shows how for known X calculate Y, not an opposite. Depends on that you may use any of formulas like

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