SOLUTION: show by a counter example that (x+y)^-2 and x^-2+y^-2 are not equivalent.

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Question 908854: show by a counter example that (x+y)^-2 and x^-2+y^-2 are not equivalent.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=1 and y=2.
x%2By=3
%28x%2By%29%5E2=9
%28x%2By%29%5E%28-2%29=1%2F9
.
.
.
x%5E2=1
x%5E%28-2%29=1
y%5E2=4
y%5E%28-2%29=1%2F4
x%5E%28-2%29%2By%28-2%29=1%2B1%2F4
x%5E%28-2%29%2By%28-2%29=5%2F4
So clearly,
%28x%2By%29%5E%28-2%29%3C%3Ex%5E%28-2%29%2By%5E%28-2%29