We can approach this problem in the following way:
1) We construct a variation equation for each variation
2) We combine these two
First variation equation would be:
[tex]y=k_1x[/tex]
This is a direct variation equation.
Second variation equation is:
[tex]g= \frac{k_2}{z} [/tex]
This is a inverse variation equation.
We combine these two by multiplying them. This will give us our final function.
Let us call it f(x,z).
[tex]f(x,z)=y(x)g(z)= \frac{k_1k_2x}{z} [/tex]
Since [tex]k_1 [/tex] and [tex]k_2[/tex] are only constants we can just combine them and call their product k.
Our final function would be:
[tex]f(x,z)=\frac{kx}{z} [/tex]
