|
|
【答案】应助回帖
没有解析解，，
>> syms x;
>> t=x+86.811
t =
x + 86811/1000
>> g=999.868+0.001*(65.85*t-8.4878*t^2+0.05607*t^3)
g =
(1317*x)/20000 - (42439*(x + 86811/1000)^2)/5000000 + (5607*(x + 86811/1000)^3)/100000000 + 691032409527619193641/687194767360000000
>> y=70025.51/g-69.11
y =
4812116405371535/(68719476736*((1317*x)/20000 - (42439*(x + 86811/1000)^2)/5000000 + (5607*(x + 86811/1000)^3)/100000000 + 691032409527619193641/687194767360000000)) - 6911/100
>> f=dsolve('Df-y=0','x')
f =
C2 + x*y
>> f=dsolve('Df-4812116405371535/(68719476736*((1317*x)/20000 - (42439*(x + 86811/1000)^2)/5000000 + (5607*(x + 86811/1000)^3)/100000000 + 691032409527619193641/687194767360000000)) - 6911/100=0','x')
Warning: Explicit solution could not be found; implicit solution returned.
> In dsolve at 201
f =
C4 + (6911*x)/100 + sum(b*log(b*((1879732970848255859375*x)/501705867264 - b*((1219322406800*x)/31438449 - 94400947489544151880849127/600120490186506240) + 9195169940350153923720578125/67513555145981952)), b in RootOf(c^3 + (3614105060076417609858987119984834826538240000000000*c)/1003161373872929637944887279366819477746996091 - 3813458196852466987999251191570737912532025274582672119140625/16435795949534079188089033185145970323406783954944, c))
>> |
|
回复此楼