How many distinct real numbers x are true for f(x)=0. Explain.

F(x)=x^2+(1/(500x^2-1000))

1 answer

x^2 + 1/(500(x^2-2)) = 0
If f(x) were x^2, then there would be a double root near 0. But, the graph is shifted down just a smidgen, so there will now be two roots near zero. Also, since there are asymptotes at ±√2, the graph will cross the x-axis near ±√2, making two more roots.

Or, we can adjust things a bit to work with a straight polynomial.

x^2 (x^2-2) + 1/500 = 0

If f(x) were x^2 (x^2-2) then there would be a double root at x=0 and roots at x = ±√2.

But our f(x) is translated up by 1/500, meaning we still have two roots near ±√2, but also now two roots near x=0. So, 4 distinct roots in all.
Similar Questions
  1. A piece of equipment has cost function C(x)=50x^2 + 1000 and its revenuefunction is R(x)= 500x - x^2, where x is in thousands of
    1. answers icon 2 answers
    1. answers icon 1 answer
  2. I have a question-The range of y = 1/(x-5) is All real Numbers True or False I think it is false because it should be all real
    1. answers icon 1 answer
    1. answers icon 17 answers
more similar questions