Find the general solution of $y(x)$ in $xe^{2y}y'-1-e^{2y}=0$
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Find the general solution of $y(x)$ in $xe^{2y}y'-1-e^{2y}=0$.
I'm just starting with diff equations and I'm having a really hard time solving them.
Here's what I've been doing:
I re-wrote the equation as:
$xe^{2y}frac{dy}{dx}-1-e^{2y}=0$, and then I ordered it as
$frac{1}{x}dx$=$frac{e^{2y}}{1+e^{2y}}dy$.
And I found the integral of both sides:
$int frac{1}{x}dx = int frac{e^{2y}}{1+e^{2y}}dy $
$ln(x)=frac{ln(e^{2y}+1)}{2}+c$.
I re-order it, and I still can't get any of the solutions... What I'm doing wrong?
calculus ordinary-differential-equations
$endgroup$
add a comment |
$begingroup$
Find the general solution of $y(x)$ in $xe^{2y}y'-1-e^{2y}=0$.
I'm just starting with diff equations and I'm having a really hard time solving them.
Here's what I've been doing:
I re-wrote the equation as:
$xe^{2y}frac{dy}{dx}-1-e^{2y}=0$, and then I ordered it as
$frac{1}{x}dx$=$frac{e^{2y}}{1+e^{2y}}dy$.
And I found the integral of both sides:
$int frac{1}{x}dx = int frac{e^{2y}}{1+e^{2y}}dy $
$ln(x)=frac{ln(e^{2y}+1)}{2}+c$.
I re-order it, and I still can't get any of the solutions... What I'm doing wrong?
calculus ordinary-differential-equations
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$begingroup$
What do the possible solutions look like?
$endgroup$
– randomgirl
Dec 20 '18 at 23:29
$begingroup$
You could write your $c$ differently like $ln(k)$ . You could then use some properties of log to rewrite your solution from there.
$endgroup$
– randomgirl
Dec 20 '18 at 23:32
add a comment |
$begingroup$
Find the general solution of $y(x)$ in $xe^{2y}y'-1-e^{2y}=0$.
I'm just starting with diff equations and I'm having a really hard time solving them.
Here's what I've been doing:
I re-wrote the equation as:
$xe^{2y}frac{dy}{dx}-1-e^{2y}=0$, and then I ordered it as
$frac{1}{x}dx$=$frac{e^{2y}}{1+e^{2y}}dy$.
And I found the integral of both sides:
$int frac{1}{x}dx = int frac{e^{2y}}{1+e^{2y}}dy $
$ln(x)=frac{ln(e^{2y}+1)}{2}+c$.
I re-order it, and I still can't get any of the solutions... What I'm doing wrong?
calculus ordinary-differential-equations
$endgroup$
Find the general solution of $y(x)$ in $xe^{2y}y'-1-e^{2y}=0$.
I'm just starting with diff equations and I'm having a really hard time solving them.
Here's what I've been doing:
I re-wrote the equation as:
$xe^{2y}frac{dy}{dx}-1-e^{2y}=0$, and then I ordered it as
$frac{1}{x}dx$=$frac{e^{2y}}{1+e^{2y}}dy$.
And I found the integral of both sides:
$int frac{1}{x}dx = int frac{e^{2y}}{1+e^{2y}}dy $
$ln(x)=frac{ln(e^{2y}+1)}{2}+c$.
I re-order it, and I still can't get any of the solutions... What I'm doing wrong?
calculus ordinary-differential-equations
calculus ordinary-differential-equations
asked Dec 20 '18 at 23:07
parishiltonparishilton
31710
31710
$begingroup$
What do the possible solutions look like?
$endgroup$
– randomgirl
Dec 20 '18 at 23:29
$begingroup$
You could write your $c$ differently like $ln(k)$ . You could then use some properties of log to rewrite your solution from there.
$endgroup$
– randomgirl
Dec 20 '18 at 23:32
add a comment |
$begingroup$
What do the possible solutions look like?
$endgroup$
– randomgirl
Dec 20 '18 at 23:29
$begingroup$
You could write your $c$ differently like $ln(k)$ . You could then use some properties of log to rewrite your solution from there.
$endgroup$
– randomgirl
Dec 20 '18 at 23:32
$begingroup$
What do the possible solutions look like?
$endgroup$
– randomgirl
Dec 20 '18 at 23:29
$begingroup$
What do the possible solutions look like?
$endgroup$
– randomgirl
Dec 20 '18 at 23:29
$begingroup$
You could write your $c$ differently like $ln(k)$ . You could then use some properties of log to rewrite your solution from there.
$endgroup$
– randomgirl
Dec 20 '18 at 23:32
$begingroup$
You could write your $c$ differently like $ln(k)$ . You could then use some properties of log to rewrite your solution from there.
$endgroup$
– randomgirl
Dec 20 '18 at 23:32
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
Just try to solve for $y$ using logarithm and exponential rules. Below, I use the notation $c$ for a constant $c in mathbb R$ not the same between each step (as well known, any form of a constant can be re-written as simply a constant) :
$$2ln(x) = ln(e^{2y}+1) + c Leftrightarrow e^{2y}+1 = e^{2ln(x)-c} Leftrightarrow e^{2y}+1 = cx^2$$
$$Leftrightarrow$$
$$e^{2y}=cx^2-1 implies y = frac{1}{2}ln(cx^2-1)$$
$endgroup$
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
add a comment |
Your Answer
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Just try to solve for $y$ using logarithm and exponential rules. Below, I use the notation $c$ for a constant $c in mathbb R$ not the same between each step (as well known, any form of a constant can be re-written as simply a constant) :
$$2ln(x) = ln(e^{2y}+1) + c Leftrightarrow e^{2y}+1 = e^{2ln(x)-c} Leftrightarrow e^{2y}+1 = cx^2$$
$$Leftrightarrow$$
$$e^{2y}=cx^2-1 implies y = frac{1}{2}ln(cx^2-1)$$
$endgroup$
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
add a comment |
$begingroup$
Just try to solve for $y$ using logarithm and exponential rules. Below, I use the notation $c$ for a constant $c in mathbb R$ not the same between each step (as well known, any form of a constant can be re-written as simply a constant) :
$$2ln(x) = ln(e^{2y}+1) + c Leftrightarrow e^{2y}+1 = e^{2ln(x)-c} Leftrightarrow e^{2y}+1 = cx^2$$
$$Leftrightarrow$$
$$e^{2y}=cx^2-1 implies y = frac{1}{2}ln(cx^2-1)$$
$endgroup$
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
add a comment |
$begingroup$
Just try to solve for $y$ using logarithm and exponential rules. Below, I use the notation $c$ for a constant $c in mathbb R$ not the same between each step (as well known, any form of a constant can be re-written as simply a constant) :
$$2ln(x) = ln(e^{2y}+1) + c Leftrightarrow e^{2y}+1 = e^{2ln(x)-c} Leftrightarrow e^{2y}+1 = cx^2$$
$$Leftrightarrow$$
$$e^{2y}=cx^2-1 implies y = frac{1}{2}ln(cx^2-1)$$
$endgroup$
Just try to solve for $y$ using logarithm and exponential rules. Below, I use the notation $c$ for a constant $c in mathbb R$ not the same between each step (as well known, any form of a constant can be re-written as simply a constant) :
$$2ln(x) = ln(e^{2y}+1) + c Leftrightarrow e^{2y}+1 = e^{2ln(x)-c} Leftrightarrow e^{2y}+1 = cx^2$$
$$Leftrightarrow$$
$$e^{2y}=cx^2-1 implies y = frac{1}{2}ln(cx^2-1)$$
answered Dec 20 '18 at 23:37
RebellosRebellos
15.5k31250
15.5k31250
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
add a comment |
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
$begingroup$
Thank you so much!!! :-)
$endgroup$
– parishilton
Dec 20 '18 at 23:58
add a comment |
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$begingroup$
What do the possible solutions look like?
$endgroup$
– randomgirl
Dec 20 '18 at 23:29
$begingroup$
You could write your $c$ differently like $ln(k)$ . You could then use some properties of log to rewrite your solution from there.
$endgroup$
– randomgirl
Dec 20 '18 at 23:32