 | 1 | initial version |
More questions about desolve results: Using
y = function('y', x)
desolve(diff(y,x) == y*(100-y), y)
results in the solution:
-1/100*log(y(x) - 100) + 1/100*log(y(x)) == _C + x
But that solution does not work for y<100. But it is correct if you assume that it should be log(abs(y(x)-100)) in the first term. Is the abs() implicit?
| | 2 | No.2 Revision |
More questions about desolve results: Using
y = function('y', x)
desolve(diff(y,x) == y*(100-y), y)
results in the solution:
-1/100*log(y(x) - 100) + 1/100*log(y(x)) == _C + x
But that solution does not work for y<100. But it is correct if you assume that it should be log(abs(y(x)-100)) in the first term. Is the abs() implicit?
(The log terms actually comes from the integral of 1/y and 1/(100-y) so it should be absolute values.)
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