Horizontal asymptote for f(x)=10x/5x^2+1

Answer 1

Using calculus, df/dx=10/(5x^2+1)-20x/(5x^2+1)^3(10x)=0

10=2/(5x^2+1)
25x^2+5=1
x^2=-4/25

x has no real solutions

Answer 2

Thank you for the help.