Weijiu Liu

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MATH 3331Ordinary Differential Equations

• Weijiu Liu
• Department of Mathematics
• University of Central Arkansas

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Why ODEs?
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Mixture Problems
Governing equation
where x denotes the amount of salt in the tank
and c is the concentration of the salt in the
inflow.
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Mass-spring Systems
Governing equation
m the mass of the object. k the stiffness of
the spring. f the external force acting on the
object.
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Population growth
Logistic population model
Where p denotes the population at time t and a,
b Are positive constants.
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Motion of Fluid Particles
Velocity
Governing equations
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Coffee in Water
Convection-diffusion equation
coffee
water