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swin2013Best ResponseYou've already chosen the best response.1
\[\lim_{x \rightarrow 3^{+}} 1/x+3\]
 one year ago

acrossBest ResponseYou've already chosen the best response.1
You have that\[\lim_{x\to3^+}\frac1{x+3}.\]Immediate substitution yields a division by zero. Therefore, you must have a vertical asymptote there. Approaching it from the right side, however, will yield \(\infty\) as the limit. On the other hand, approaching it from the left side will yield \(\infty\) as the limit.
 one year ago

ksaimouliBest ResponseYou've already chosen the best response.1
i am soory i read it wrong
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
since it is on the right side, do i write that the limit is approaching positive infinity?
 one year ago

ksaimouliBest ResponseYou've already chosen the best response.1
actually the limit DNE because the absolute value get very large
 one year ago

acrossBest ResponseYou've already chosen the best response.1
Because it's a sided limit, you have to specify \(\text{where}\) it goes. Simply writing DNE won't suffice.
 one year ago

viniterranovaBest ResponseYou've already chosen the best response.0
I got it 1/6. Just plug it into the equation
 one year ago

acrossBest ResponseYou've already chosen the best response.1
@viniterranova, how did you get \(1/6\)?
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
I'm pretty sure i should get either  infinity or positive. I'm kind of unclear on what to write. I understand that when i divide the constant (1) by x2 (which is a small positive number), does that mean it's approaching positive infinity since 1 / x2 is getting positively bigger?
 one year ago

viniterranovaBest ResponseYou've already chosen the best response.0
http://www.wolframalpha.com/input/?i=limit+x%3E+3%2B+%281%2F%28x%2B3%29
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
@viniterranova it's actually negative 3. it appears that the equation plugged in 3. if we plug in the value of 3, we get 0 on the denominator which is not valid since the denominator can't be zero
 one year ago

acrossBest ResponseYou've already chosen the best response.1
@swin2013, when you're asked to compute\[\lim_{x\to3^+}\frac1{x+3},\]if you substitute the limit, \(3\), you'll have that\[\frac1{x+3}=\frac1{(3)+3}=\frac10.\]Therefore, you know that the limit DNE. However, if you approach \(3\) from the right side, you'll have that\[\frac1{x+3}\]gets infinitely larger (since you're dividing by a really small number) toward \(\infty\). Oh, and @viniterranova, the limit is \(3\), not \(3\). Read the question again.
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
so am i correct in the sense that x  infinity?
 one year ago

viniterranovaBest ResponseYou've already chosen the best response.0
See teh wolfram site.
 one year ago

viniterranovaBest ResponseYou've already chosen the best response.0
The fact of you have the minus sign after 3 doesn´t mean that the 3 is negative. Just mean that you are approaching from left.
 one year ago

acrossBest ResponseYou've already chosen the best response.1
No, you silly, \(3\) is different from \(3^\).
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
no. if it's approaching 3 to the left, there will be a negative as an exponent
 one year ago

acrossBest ResponseYou've already chosen the best response.1
@swin2013, for example, let \(k=2.99999\) be that close to \(3\). Then\[\frac1{k+3}=\frac1{2.99999+3}=\frac1{0.00001}=100,000.\]So you indeed approach \(\infty\).
 one year ago

acrossBest ResponseYou've already chosen the best response.1
(Notice that we're close to it from the right side.)
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
thank you @across, i just need clarity on what to write for my answer haha. I already understand the concept :)
 one year ago

viniterranovaBest ResponseYou've already chosen the best response.0
Across you didn´t understand me. I just said minus sign after 3 not before.
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
yea but the equation never stated a negative sign after the 3.
 one year ago

acrossBest ResponseYou've already chosen the best response.1
That doesn't change the fact that you screwed up, @viniterranova. ;) @swin2013, you can write: "The limit does not exist as it approaches positive infinity."
 one year ago

acrossBest ResponseYou've already chosen the best response.1
You can also just write\[\lim_{x\to3^+}\frac1{x+3}=\infty.\]It depends on your teacher.
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
x  infinity no finite lim :)
 one year ago

ksaimouliBest ResponseYou've already chosen the best response.1
the correct way to say according to textbook is it DNE
 one year ago

acrossBest ResponseYou've already chosen the best response.1
lol @ksaimouli, you are right, but this is a SIDED LIMIT. In other words, YOU MUST SPECIFY WHERE IT IS GOING. <:)
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
lol i never said INFINITE i said FINITE
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
which is the same as DNE as in there is not possible limit
 one year ago

swin2013Best ResponseYou've already chosen the best response.1
or DEFINITE limit (the derivative of FINITE)
 one year ago
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