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location B.C., Canada
age 24
visits member for 2 years
seen Oct 17 at 5:56

Oct
17
comment Solve ODE by substitution
$dx$ and $du$ mean to integrate with respect to $x$ and $u$ so why can't you have $\int x du$ and treat $x$ as a constant?
Oct
16
comment Solve ODE by substitution
"You cannot directly integrate ∫xdu without proir knowledge of what x is as a function of u" could you please explain why? Is it because if you have some random variable, call it w and you integrate it with respect to some other random variable, call it v then it doesn't work? But it's ok for constants?
Oct
15
comment Solve ODE by substitution
or am I not allowed to integrate like that?
Oct
15
comment Solve ODE by substitution
this would give the answer $ux+x=0 \Rightarrow y=-x$
Oct
15
comment Solve ODE by substitution
why did you factor out $x^2$ instead of $x$ to get $x(xdu + dx)=0$ ?
Oct
15
comment Solve ODE by substitution
How do you get $\frac{dx}{x}+du=0$?
Oct
14
asked Solve ODE by substitution
Oct
9
comment What's the easiest way to approximate an answer to n places after the decimal?
Yes more towards your second point, I want max percision but sometimes want to see a decimal answer (even though I know it would be an approximation) so lprint sounds like a good option.
Oct
9
comment Do mathematicians, in the end, always agree?
-1 saying people in the field of mathematics agree with each other, and people in a field of science's disagree with each other is immature and foolish.
Oct
2
comment What's the easiest way to approximate an answer to n places after the decimal?
@GerryMyerson You mean Digits:=2 and then the expression evalf(19/4, 2) nope that didn't work, that just assigns 2 to the variable digits.
Oct
2
asked What's the easiest way to approximate an answer to n places after the decimal?
Oct
2
awarded  Yearling
Sep
25
comment why isn't this part of the equation considered transient?
"It's the $e^x$ term that dominates the first limit" how can you prove this? I considered L'Hospital's rule but $x^{-2}$ gets bigger where $e^x$ remains the same.
Sep
25
asked why isn't this part of the equation considered transient?
Sep
24
asked Specifying variables in Maple
Sep
8
comment What is the interval of definition of a solution of an ODE?
Oh so you could say $(-\infty, 1)$ or $(1, \infty)$ just not both?
Sep
8
comment What is the interval of definition of a solution of an ODE?
For $y(t)=1/(t-1)$ why wouldn't the interval be $(-\infty,1)\cup (1,\infty)$? Shouldn't it be anything that does not make the denominator 0?
Sep
8
asked What is the interval of definition of a solution of an ODE?
Sep
6
asked Is this ODE linear?
Sep
6
asked Definition of ordinary differential equation