(rational function) f(x)=x-4/(x^2)-16. when i plug in f(4), i should get (4,0) as a point on a graph... but according to my graphing calculator, i dont. WHY!!?!

Question

anonymous · Answer

yes i am aware that seeing as n>m, there is a horizontal asymptote at y=0. but isnt that a contradiction to the function when you plug in 4 as an x value? when i plug in 4, i get 0/0 everytime... which isnt undefined... why??

jhonyy9 · Answer

so x not can being equal 4 or -4 because than this fraction will have denominator zero and than this will be undefined

anonymous · Answer

but wait

anonymous · Answer

x-4 is on top... so when you plug in 4 for the function, the top will = 0!

anonymous · Answer

therefore the whole f(4) = 0