Here's the question you clicked on:
onegirl
Use graphical and numerical evidence to conjecture a value for the indicated limit.
lim x -> infinity sign x^2/2^x
Did you plug in some large numbers like x=50,100,1000 and see what happens to y values for the function f=sign x^2/2^x ?
i havent but i'll try that
Also I'm not totally sure how to read your function....but that it the way you approximate this limit numerical style.