Solving the Initial Value Problem for x'=x^3 with x(0)=1

Then x = (-2t - c)^{-1/2}.In summary, to solve the initial value problem x'=x^3 x(1)=1, we first integrated dx/x^3 = dt to obtain x^(-2) = t + c. Simplifying, we get 1/x = sqrt(t+c), which leads to x = 1/sqrt(t+c). However, when applying the initial value, we get c = 0, which is incorrect. The correct solution is x = (-2t-c)^(-1/2).
  • #1
simo1
29
0
solve the initial value problem:
x'=x^3 x(1)=1

my work

dx/x^3 =dt
then I integrated wrt t and obtained
x^(-2) = t + c(c0nstant)
where then
this is 1/x^2 =t+c
1/x = square root of (t+c)
then
x= 1/sqrt(t+c)

now when i apply the Initial value problem i get c = 0 and that is incorrect. where am i going wrong
 
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  • #2
the intergral of x^-3 is (1/2)multiply by 1/x^2=t+c
then your constant value will be 3:)
 
  • #3
onie mti said:
the intergral of x^-3 is (1/2)multiply by 1/x^2=t+c
then your constant value will be 3:)

Actually it's -(1/2)(1/x^2), or -(1/2)x^{-2}
 

Related to Solving the Initial Value Problem for x'=x^3 with x(0)=1

What is an initial value problem?

An initial value problem is a type of mathematical problem that involves finding a function (or set of functions) that satisfies a given differential equation, along with a set of initial conditions. These initial conditions specify the values of the function(s) at a certain point or points in the domain.

What types of equations can be solved using initial value problems?

Initial value problems can be used to solve a variety of differential equations, including first-order equations, higher-order equations, and systems of equations. These equations can be either ordinary differential equations (ODEs) or partial differential equations (PDEs).

Why are initial value problems important?

Initial value problems are important because they allow us to model and understand a wide range of real-world phenomena. Many physical, biological, and economic processes can be described using differential equations, and initial value problems provide a way to solve these equations and predict the behavior of these systems.

What are the main steps involved in solving an initial value problem?

The main steps in solving an initial value problem include writing down the given differential equation, determining the order of the equation, finding the general solution, applying the initial conditions to find the particular solution, and checking the solution for accuracy.

What are some common methods for solving initial value problems?

Some common methods for solving initial value problems include separation of variables, variation of parameters, undetermined coefficients, and Laplace transform. These methods can be used to solve first-order and second-order ODEs as well as systems of equations.

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