Solve Differential Equation 2: $fracd^2ydx^2-2xfracdydx+2y=0$ [closed]
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solve $fracd^2ydx^2-2xfracdydx+2y=0$
I tried to solve through linear differential equation but it has variable with x in first derivative .
differential-equations
closed as off-topic by Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus Jul 21 at 0:03
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." â Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus
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up vote
-2
down vote
favorite
solve $fracd^2ydx^2-2xfracdydx+2y=0$
I tried to solve through linear differential equation but it has variable with x in first derivative .
differential-equations
closed as off-topic by Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus Jul 21 at 0:03
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." â Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus
add a comment |Â
up vote
-2
down vote
favorite
up vote
-2
down vote
favorite
solve $fracd^2ydx^2-2xfracdydx+2y=0$
I tried to solve through linear differential equation but it has variable with x in first derivative .
differential-equations
solve $fracd^2ydx^2-2xfracdydx+2y=0$
I tried to solve through linear differential equation but it has variable with x in first derivative .
differential-equations
edited Jul 20 at 18:57
Nosrati
19.5k41544
19.5k41544
asked Jul 20 at 18:55
ravi yadav
295
295
closed as off-topic by Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus Jul 21 at 0:03
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." â Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus
closed as off-topic by Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus Jul 21 at 0:03
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." â Nosrati, Shaun, Adrian Keister, Taroccoesbrocco, Leucippus
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2 Answers
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2
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accepted
Substituting $$y=xv$$ then we get $$y'=xv'+v$$ and $$y''=xv''+2v'$$ then our equation will be
$$xv''-2v'(x^2-1)=0$$ now we Substitute
$$v'=u$$ then we get $$fracu'u=-frac2x+2x
$$
and we get
$$intfracu'udx=intleft(-frac2x+2xright)dx$$
this gives
$$log(u(x))=x^2-log(x)+C$$
Can you finish?
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
1
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
add a comment |Â
up vote
2
down vote
$y=c_1x$ is a solution.
You can try to integrate the differential by reduction of order
Try
$$y_1=v(x)x$$
The original equation
$$y''-2xy'+2y=0$$
becomes
$$v''x+2v'(1-x^2)=0$$
Substitute $w=v'$
$$w'x+2w(1-x^2)=0$$
It's a first order,differential equation
$$(ln w)'=2x-frac 2x$$
$$ln w=x^2-2ln x + K$$
$$w=C_1frac e^x^2x^2$$
$$v'=C_1frac e^x^2x^2$$
$$v(x)=C_1int frac e^x^2x^2dx+C_2$$
$$y(x)=C_1xint frac e^x^2x^2dx+C_2x$$
$$boxedy(x)=C_1(xsqrt pitext erfi(x)-e^x^2)+C_2x$$
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
2
down vote
accepted
Substituting $$y=xv$$ then we get $$y'=xv'+v$$ and $$y''=xv''+2v'$$ then our equation will be
$$xv''-2v'(x^2-1)=0$$ now we Substitute
$$v'=u$$ then we get $$fracu'u=-frac2x+2x
$$
and we get
$$intfracu'udx=intleft(-frac2x+2xright)dx$$
this gives
$$log(u(x))=x^2-log(x)+C$$
Can you finish?
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
1
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
add a comment |Â
up vote
2
down vote
accepted
Substituting $$y=xv$$ then we get $$y'=xv'+v$$ and $$y''=xv''+2v'$$ then our equation will be
$$xv''-2v'(x^2-1)=0$$ now we Substitute
$$v'=u$$ then we get $$fracu'u=-frac2x+2x
$$
and we get
$$intfracu'udx=intleft(-frac2x+2xright)dx$$
this gives
$$log(u(x))=x^2-log(x)+C$$
Can you finish?
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
1
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
add a comment |Â
up vote
2
down vote
accepted
up vote
2
down vote
accepted
Substituting $$y=xv$$ then we get $$y'=xv'+v$$ and $$y''=xv''+2v'$$ then our equation will be
$$xv''-2v'(x^2-1)=0$$ now we Substitute
$$v'=u$$ then we get $$fracu'u=-frac2x+2x
$$
and we get
$$intfracu'udx=intleft(-frac2x+2xright)dx$$
this gives
$$log(u(x))=x^2-log(x)+C$$
Can you finish?
Substituting $$y=xv$$ then we get $$y'=xv'+v$$ and $$y''=xv''+2v'$$ then our equation will be
$$xv''-2v'(x^2-1)=0$$ now we Substitute
$$v'=u$$ then we get $$fracu'u=-frac2x+2x
$$
and we get
$$intfracu'udx=intleft(-frac2x+2xright)dx$$
this gives
$$log(u(x))=x^2-log(x)+C$$
Can you finish?
answered Jul 20 at 19:10
Dr. Sonnhard Graubner
66.8k32659
66.8k32659
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
1
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
add a comment |Â
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
1
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
yes , thank you very much
â ravi yadav
Jul 20 at 19:12
1
1
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
Then good luck Mr. Ravi (like Ravi Substitution?)
â Dr. Sonnhard Graubner
Jul 20 at 19:13
add a comment |Â
up vote
2
down vote
$y=c_1x$ is a solution.
You can try to integrate the differential by reduction of order
Try
$$y_1=v(x)x$$
The original equation
$$y''-2xy'+2y=0$$
becomes
$$v''x+2v'(1-x^2)=0$$
Substitute $w=v'$
$$w'x+2w(1-x^2)=0$$
It's a first order,differential equation
$$(ln w)'=2x-frac 2x$$
$$ln w=x^2-2ln x + K$$
$$w=C_1frac e^x^2x^2$$
$$v'=C_1frac e^x^2x^2$$
$$v(x)=C_1int frac e^x^2x^2dx+C_2$$
$$y(x)=C_1xint frac e^x^2x^2dx+C_2x$$
$$boxedy(x)=C_1(xsqrt pitext erfi(x)-e^x^2)+C_2x$$
add a comment |Â
up vote
2
down vote
$y=c_1x$ is a solution.
You can try to integrate the differential by reduction of order
Try
$$y_1=v(x)x$$
The original equation
$$y''-2xy'+2y=0$$
becomes
$$v''x+2v'(1-x^2)=0$$
Substitute $w=v'$
$$w'x+2w(1-x^2)=0$$
It's a first order,differential equation
$$(ln w)'=2x-frac 2x$$
$$ln w=x^2-2ln x + K$$
$$w=C_1frac e^x^2x^2$$
$$v'=C_1frac e^x^2x^2$$
$$v(x)=C_1int frac e^x^2x^2dx+C_2$$
$$y(x)=C_1xint frac e^x^2x^2dx+C_2x$$
$$boxedy(x)=C_1(xsqrt pitext erfi(x)-e^x^2)+C_2x$$
add a comment |Â
up vote
2
down vote
up vote
2
down vote
$y=c_1x$ is a solution.
You can try to integrate the differential by reduction of order
Try
$$y_1=v(x)x$$
The original equation
$$y''-2xy'+2y=0$$
becomes
$$v''x+2v'(1-x^2)=0$$
Substitute $w=v'$
$$w'x+2w(1-x^2)=0$$
It's a first order,differential equation
$$(ln w)'=2x-frac 2x$$
$$ln w=x^2-2ln x + K$$
$$w=C_1frac e^x^2x^2$$
$$v'=C_1frac e^x^2x^2$$
$$v(x)=C_1int frac e^x^2x^2dx+C_2$$
$$y(x)=C_1xint frac e^x^2x^2dx+C_2x$$
$$boxedy(x)=C_1(xsqrt pitext erfi(x)-e^x^2)+C_2x$$
$y=c_1x$ is a solution.
You can try to integrate the differential by reduction of order
Try
$$y_1=v(x)x$$
The original equation
$$y''-2xy'+2y=0$$
becomes
$$v''x+2v'(1-x^2)=0$$
Substitute $w=v'$
$$w'x+2w(1-x^2)=0$$
It's a first order,differential equation
$$(ln w)'=2x-frac 2x$$
$$ln w=x^2-2ln x + K$$
$$w=C_1frac e^x^2x^2$$
$$v'=C_1frac e^x^2x^2$$
$$v(x)=C_1int frac e^x^2x^2dx+C_2$$
$$y(x)=C_1xint frac e^x^2x^2dx+C_2x$$
$$boxedy(x)=C_1(xsqrt pitext erfi(x)-e^x^2)+C_2x$$
edited Jul 20 at 19:52
answered Jul 20 at 19:07
Isham
10.6k3829
10.6k3829
add a comment |Â
add a comment |Â