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View Full Version : [SOLVED] need help understanding How to invert number. please



estatefinds
08-02-2016, 10:34 AM
I want to do something similar with values but need help on how to achieve how to invert values that they discuss in here.



In the speardsheet alongside, we placed 1 in A1. In B1 we invert the value of A1. In C1 we add one to the value in B1. In D1, we invert the value in C1. In A2, we add 1 to the value in D1 and copy all these formulae downwards. You can see how quickly the result in column A becomes the Golden Ratio.
Important: This result does not depend on the first entry. One can place any value other than 0 into A1 and the process will work. Below you can see that the number 50 in A1 produces the Golden ratio in just 9 steps.
http://jwilson.coe.uga.edu/EMAT6680/Brink/allasgnmts/Graphs12/image29.gif


http://jwilson.coe.uga.edu/EMAT6680/Brink/allasgnmts/Graphs12/image28.gif


I will attach file when I return home Thank you in advance for your help!:)

SamT
08-02-2016, 11:12 AM
B1 Formula
=If(A1<>0),(1/((1/A1)+1)+1),0)

A2 Formula
=If(B1<>0,B1+1,0)

Fill Down both.

BTW, Excel calculates to 15 decimal places, although with rounding errors in the 15th.

estatefinds
08-02-2016, 11:38 AM
Thank you!!! I prepare worksheet when I get home.
Does this include the C. And D columns?

SamT
08-02-2016, 12:01 PM
Does this include the C. And D columns?
No. All the math from B to D is included in the B1 formula.

If("Cell" <> 0, . . . is error prevention. If A1 is a zero, all cells with formulas will display zeros to indicate that they are working

estatefinds
08-02-2016, 03:15 PM
When i enter the formaula B1 Formula
=If(A1<>0),(1/((1/A1)+1)+1),0)


I get " the formula you typed contains an error"

Tried removing a parenthesis after the =if(A1<>0,(1/((1/A1)+1)+1),0)

and no error occurred is this correct? I just want to make sure results are accurate.

estatefinds
08-02-2016, 05:05 PM
ok Im adding file.
I placed the number 1 and the result is only in column B but not in C and D. Can this file im sending mimic what i see in the original post?
I want work with it to get it what i want to do with My data. its not giving me the 1.618

Thank you

SamT
08-02-2016, 05:42 PM
Yeah, there was an extra +1 in my original B1 formula

If you must have all four columns, to invert a number just divide 1 by the number (=1/A1)

To ignore all columns except Column A:

If you just want to show the progression from A1 to the Golden Ratio, place this formula in A2 and copy it down.
=IF(A1<>0,(1/((1/A1)+1)+1),0)

Then, if you want to the results to indicate when the Golden Ratio is reached as far as Excel can take it, place this one in A3 and copy it down to about A25.
=IF(A2=A1,,IF(A2<>0,(1/((1/A2)+1)+1),))

estatefinds
08-02-2016, 06:43 PM
Thank you I got it working! the formula B1 i tried removing the +1 and kept getting error. so i replaced the +1 and I then removed parenthese after the first Zero and it worked again.

Great job helping me on this thanks again!:)