Question 312848
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"jointly" as x and z -- x and z go in the numerator


"inversely" as w -- w goes in the denominator


Throw in a constant of proportionality, generally a k will do, and you have it:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y\ =\ \frac{kxz}{w}]


Plug in what you know for the initial conditions:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{3}{2}\ =\ \frac{k(2)(2)}{(4)}]


Which is to say:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ k\ =\ \frac{3}{2}]


and finally:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y\ =\ \frac{3xz}{2w}]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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