quasi
Posts:
12,067
Registered:
7/15/05


Re:     validity of an equation
Posted:
Mar 2, 2013 3:08 PM


You removed the relevant context, so I'll remove still more.
In the reply you snipped, I showed:
If x,y,z are integers such that
y^(1/2) = (x^10  z^5)^(1/5)
then, letting w = x^10  z^5, the equation reduces to
y^5 = w^2
which implies y is a perfect square and w is a perfect 5'th power.
Now you ask, what if we assume that y is not a perfect square?
Then you get a contradiction, of course.
A triviality.
quasi

