I need to isolate A_0 in a payment formula with CAS. I'm using GNU Maxima.
The solution is suppose to be A_0 = 102025
Using solve():
solve ((A_0*0.06)/(1-(1.06)^9)=15000, A_0), numer;
rat: replaced -0.08702223500306361 by -14658597/168446570 = -0.08702223500306358
rat: replaced -0.08702223500306358 by -14658597/168446570 = -0.08702223500306358
rat: replaced -1.780980164808343e-8 by -3/168446570 = -1.780980164808343e-8
rat: replaced 172369.7397506733 by 14849997819/86152 = 172369.7397506732
[A_0=-172369.7397506732]
Using find_root:
find_root ((A_0*0.06)/(1-(1.06)^9)=15000, A_0, 100000, 120000)
find_root: function has same sign at endpoints: f(100000.0)=-23702.22350030636, f(120000.0)=-25442.66820036763
-- an error. To debug this try: debugmode(true);
PS. I know am I am not finding a root but I thought why not? I got it working before with help in Understanding simple solve equation output from Maxima
Maxima version: 5.43.0 (x86_64-apple-darwin13.4.0)
EDIT: Nevermind! I wrote the formula wrong! I missed that the exponentiation is suppose to me in minus.
It was suppose to be:
solve ((A_0*0.06)/(1-1.06^-9)=15000), numer
[A_0=102025.3841174938]
