Help differential equations anyone?

rainyrabbit
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Homework Statement



Differential equation: dx/dt = 1000 + 0.10x
x(0) = 1000
Solve the initial value problem for x as a function of t

Section of Exponential/Logistic growth; applications (population growth) ---- Intro-level calculus


Homework Equations



Answer: x = 11000e^(0.1t) - 10,000

The Attempt at a Solution



Sorry could you help me how this answer (found at the end of the book) is gotten? Sorry but I do not know how to do it; please help. ^^
 
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Separate the variables.
 
Have you tried actually reading the book? I don't mean to be harsh but there are several different ways to solve this equation and I don't know which one you are to learn at this point in your course. If you are at the beginning of the course then probably the simplest thing to do is what neutrino suggested: separate variables.
From \frac{dx}{dt}= 1000- 0.10x you can easily get
\frac{dx}{1000- 0.10x}= dt and integrate.
 
hah stupid of me thx. for your help.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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