Limit[x^0.5 ((x + 4)^0.5 - x^0.5), x -> ∞] 1. does not exist 2. exists and is equal to 0 3. exists and is equal to 1/2 4. exists and is equal to 2 (The answer is given as D. But how to proove it? )
Follow Math Help Forum on Facebook and Google+
you sure the answer isn't -2? or the limit goes to 0?
yes. the answer is 2. (and NOT -2)
why don't you try to graph it with a software? I am pretty sure the limit approches to -2, if there is no mistake in the paranthesis,
yes. graphing software show that the limit appproaches 2. Plot[x^0.5` (-x^0.5` + (4 + x)^0.5`), {x, -10, 10}]
oki, here is my solution. I multiplied and divided the term with the conjugate of the second part of the equation. then used L'hospital. Because it is inf/inf.
With simple manipulations you obtain... But... ... so that... Kind regards
impressed with the use of symbols.
Originally Posted by sench impressed with the use of symbols. You also can learn LaTeX
View Tag Cloud