## Easy and True

Posted by ragknot on February 6, 2016 – 2:41 pm

Solve this equation …X=A*LOG(B*X+D)

A=12, B= 4, and D=7, learn the X.

It is easy and true in Excel. Type a guess of X in a cell A1, then below the guess, type … =12*Log(4*A1+7) Then copy the cell A2 to about 30 cells. An the X number will change until the X is right. It will stop changing when it can use the lots of equations.

March 1st, 2016 at 8:12 pm

A=12 B=4 D=7

First X = (in A1)

1 Difference in cells of A1

12.95017495 12*LOG(4+A1+7)= 11.95017495

16.55170428 and copy the A2 to= 3.60152933

17.28178162 next copy is = 0.730077339

17.41808117 0.136299553

17.44313701 0.025055831

17.44772992 0.004592913

17.44857139 0.000841475

17.44872555 0.000154153

17.44875379 2.82395E-05

17.44875896 5.1732E-06

17.44875991 9.47679E-07

17.44876008 1.73606E-07

17.44876011 3.18028E-08

17.44876012 5.82597E-09

17.44876012 1.06726E-09

17.44876012 1.95513E-10

17.44876012 3.58149E-11

17.44876012 6.56186E-12

17.44876012 1.20082E-12

17.44876012 2.20268E-13

17.44876012 4.26326E-14

17.44876012 0

17.44876012 0

17.44876012 0

17.44876012 0

17.44876012 0

17.44876012 0

17.44876012 0

March 8th, 2016 at 1:05 pm

Ragknot, try to find the solution x = 30 to the equation

x = 30 LOG( x – 20 )

using your approach, and with a starting value of x near 30, but slightly different.