Implicit Function Theorem problem

KevinMWHM
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Part 1. If I want to solve the system;

u-v = (h-a)e^-s

w-u = (k-b)e^-t

ae^s = be^t

for a, b, u, in terms of the remaining variables using the implicit function theorem...

If I want to know when I can solve, can I just say f(a, b, u) can not = 0? And if I set a, b, u, = 0

Than I get k and h can not = 0.
Part 2. Calculate du/ds, da/ds, db/ds, by exhibiting a linear set of equations.

So for da/ds for example, solve equation 1 for a giving;

d(-e^s(u-v)+h)/ds?
I don’t need to solve the system.
 
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KevinMWHM said:
Part 1. If I want to solve the system;

u-v = (h-a)e^-s

w-u = (k-b)e^-t

ae^s = be^t

for a, b, u, in terms of the remaining variables using the implicit function theorem...

If I want to know when I can solve, can I just say f(a, b, u) can not = 0? And if I set a, b, u, = 0

Than I get k and h can not = 0.
Part 2. Calculate du/ds, da/ds, db/ds, by exhibiting a linear set of equations.

So for da/ds for example, solve equation 1 for a giving;

d(-e^s(u-v)+h)/ds?
I don’t need to solve the system.

For Part 1, you don't NEED to solve the system, but the easiest solution is to just go ahead and solve it anyway! Using the notation ##S = e^{-s}## and ##T = e^{-t}##, write your equations as
u-v = (h-a)S\\<br /> (w-u)=(k-b) T \\<br /> a/S = b/T<br />
This is a simple linear system, from which you can easily find ##a,b,u## in terms of ##v,w,h,k,S,T##.

For Part 2, you can also derive a simple linear system for ##\partial a/ \partial s, \: \partial b / \partial s, \: \partial u / \partial s## and get a solution in terms of ##a,b,u,v,w,h,k,S,T##, using the definitions of ##S,T## in terms of ##s,t##.
 
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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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