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

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SUMMARY

The discussion focuses on solving the initial value problem for the differential equation x' = x^3 with the condition x(0) = 1. The user initially integrates the equation incorrectly, leading to an erroneous constant value. The correct integration yields x = 1/sqrt(t + c), where the constant c must be determined accurately. The correct integral of x^-3 is -(1/2)x^{-2}, which clarifies the miscalculation in determining the constant.

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simo1
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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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the intergral of x^-3 is (1/2)multiply by 1/x^2=t+c
then your constant value will be 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}
 

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