🚀 go-pugleaf

"Chris Harding" <pouchcotato@iinet.net.au> writes:

> I have this equation that I need to be changed around, but have no idea how
> to do it. In letters, the equation is (sorry for the numerous brackets, but
> it's hard without pen and paper abilities on here):
> 
> Y = A � (((B�100)�D) + 1)^(C�D)
> 
> And what I need is for the equation to become like this:
> 
> A= Y � (((B�100) � D) +1)^(C�D)
> 
> but for B=... C=... and D=...
> 

Starting with y=a(b/100d + 1)^c/d

First step by step for b:

divide both sides by a: y/a = (b/100d + 1)^c/d
raise both to d/c     : (y/a)^d/c = b/100d + 1
subtract 1            : (y/a)^d/c -1 = b/100d
multiply by 100d      : 100d((y/a)^d/c -1) = b

All you need to do this is a good grasp of algebra.

Now step by step for c:

divide both sides by a       : y/a = (b/100d + 1)^c/d
take logs                    : log(y/a) = (c/d) log(b/100d + 1)
multiply by d/log(b/100d + 1): d log(y/a)/log(b/100d + 1) = c 

Here you also need to know a little about logs.

d is much harder ... I'm not sure it is possible to solve for d
algebraically. I can't, at any rate.

Glen.