# Math Help - Finding the Limit

1. ## Finding the Limit

can someone explain to me how sqrt(x^2 + x^4) became sqrt(1+x^2)?

2. ## Re: Finding the Limit

Originally Posted by l flipboi l
can someone explain to me how sqrt(x^2 + x^4) became sqrt(1+x^2)?
You can factor out an x^2 from the expression under the square root: $\sqrt{x^2(1+x^2)}$ and, by the laws of surds, $\sqrt{x^2}\sqrt{1+x^2} = |x|\sqrt{1+x^2}$

The |x| which is now outside the radical is cancelled with the x in the numerator. (They have said that $\sqrt{x^2} = x$ before cancelling which is OK if x>0[/tex]