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Hey, PF:
If I have a function ##f(x)## where ##x## is itself a function of another variable (say time), is the following then true? $$f(x)=f(x(t))=f(t)$$
I ask this because if I have the following system of differential equations
$$\frac{dA}{dt}=-Bb$$
$$\frac{dB}{dt}=-Aa$$
where litte ##a## and ##b## are constants, and I solve for ##B(t)## and ##A(t)## as functions of ##t## and solve for ##B(A)## and ##A(B)## as functions of each other, can I reduce ##A(B)## to ##A(t)##?
In my mind, it makes sense that $$\begin{align} B(A)=&B(A(t)) \\ =&B(t)\end{align}$$ If this is in fact true, what is this process, or principle, called?
Here's the link outlining the problem:
http://courses.ncssm.edu/math/POW/POW07_08/Calculus%20Challenge%20%2314%20SOLUTION.pdf
I'm specifically trying to understand how ##A(t)## on pg. 4 relates to ##A## (As a function of ##B##) on page 5.
Please keep in mind that my background in math is limited to some multivariable calculus and some ordinary differential equations.
Thank you,
If I have a function ##f(x)## where ##x## is itself a function of another variable (say time), is the following then true? $$f(x)=f(x(t))=f(t)$$
I ask this because if I have the following system of differential equations
$$\frac{dA}{dt}=-Bb$$
$$\frac{dB}{dt}=-Aa$$
where litte ##a## and ##b## are constants, and I solve for ##B(t)## and ##A(t)## as functions of ##t## and solve for ##B(A)## and ##A(B)## as functions of each other, can I reduce ##A(B)## to ##A(t)##?
In my mind, it makes sense that $$\begin{align} B(A)=&B(A(t)) \\ =&B(t)\end{align}$$ If this is in fact true, what is this process, or principle, called?
Here's the link outlining the problem:
http://courses.ncssm.edu/math/POW/POW07_08/Calculus%20Challenge%20%2314%20SOLUTION.pdf
I'm specifically trying to understand how ##A(t)## on pg. 4 relates to ##A## (As a function of ##B##) on page 5.
Please keep in mind that my background in math is limited to some multivariable calculus and some ordinary differential equations.
Thank you,