When calculating the limit of the function f(x) = (x^2 + 3)/ sqrt(2x^4 + 5) as x→∞, is it correct to square the top and then place the resulting polynomial under a square root (i.e. sqrt(x^2 + 3)^2)? Then you can rewrite the problem as the square root of the limit as x→∞ of the resulting function. So, you'll have: sqrt(lim x→∞ (x^2 + 3)/ (2x^4 + 5)) Divide above and below by x^4 and solve. Thanks.