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anonymous
 5 years ago
what is this limit
\[\lim_{x \rightarrow \pi/2}(xcosx)\]
anonymous
 5 years ago
what is this limit \[\lim_{x \rightarrow \pi/2}(xcosx)\]

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\lim_{x \rightarrow \pi/2}(xcosx)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0mertsj do you mind demonstrating that please?

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3pi/2times cospi/2=pi/2times 0 = 0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok thanks would you mind helping me with this one also

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\lim_{x \rightarrow 7}(x^2 + 10x + 21/x + 7)\] i've got 98/0. i dont know what to do from there

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3You can't divide by 0 so divide numerator so another approach is needed.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok i was thinking along the lines as approach 7 from left and right

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0(x+7)(x+3)/(x+7)...so the x + 7 cancels and im left with x + 3

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3Now replace the x with 7

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have this one that is somewhat similar but you end up with 0/0 \[\lim_{x \rightarrow 1}(x^2  4x + 3/ x^2 + 2x 3)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0same approach again right? factor and reduce?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0(x3)(x1)/ (x3)(x+1)...?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0is that the right structure

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh wow im getting this thanks for the help. would you be willing to continue working with me? i have about 8 more

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3I am willing but I might be a little distracted as my daughter is here and we are visiting.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\lim_{x \rightarrow 10}(x^2  17x + 70/ x + 10)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0when i attempt this...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i get 140/0...so i take the factor and reduce approach

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0(x+10)(x+7)/ (x+10)....x+7...10+7= 3?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i keep getting my signs wrong when i factor

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3It won't reduce. Did you copy it right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why couldnt it have been (x+10)(x+7)...it will also give you 70 right

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah thats right i remember now

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3Perhaps you wrote the problem down incorrectly

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah now i understand

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have this next one...

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3Did you get that last one?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\lim_{x \rightarrow 2}(x^2  4/2x^2 5x + 2)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I got DNE (does not exist) my software accepted the answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how exactly would you factor the denominator in the previous problem. it is set up strangely for me

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3That one should factor and reduce.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok i was confused because i thought somehow it must add up to 5

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3So you end up with (x+2)/(2x1)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\lim_{x \rightarrow 4}(\sqrt{b+0}2/b4)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0do you still factor here? doesnt look like it

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3It won't factor but why does it have sqrt(b+0) since that is just sqrt(b)?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0its sqrt (b +0)...i would guess you do 4 +0 then squared root your answer then subtract 2

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3But the denominator will be 0 and that is undefined.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah i got 0/0 i was thinking theres something we could do next

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3multiply the numerator and denominator by (sqrt(b)+2)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if the numerator and denominator are both zeros. wouldnt mulitplying bring us back to square 1 with 0/0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0dw:1326946154087:dw

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the limit is as x approaches 9

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3Multiply numerator and denominator by 9x

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3lim as x approaches 9 is 1/81

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0thanks im almost through

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Let 11x−36≤f(x)≤x2+5x−27 . Use the Squeeze Theorem to determine limx→3f(x) =

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3ok but I still want to revisit that DNE one

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok when we finish we can go back

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0this one that i posted is a new concept so its unlike what we have been practicing so im clueless

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3I see that. I have never heard of the squeeze theorem but I would assume that we should evaluate both expressions when x is 3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i got 33 and 3 respectively. what do i do with these two numbers to come up with a final answer

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3You should get 3 for both of them and that is the limit. I just read it on the internet.

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3redo the one you got the 33 for

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah you're right i entered it incorrectly in my calculator

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0dw:1326947257959:dw as x approaches 0

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3I'm not sure about this one. Unless you use a reduction formula of some sort.

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3Have you tried typing it into wolframalpha?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0L'hospital does this one easily

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0dw:1326947625929:dw

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3I'll turn you over to Turing now.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0thanks for all the help Mertsj I really appreciate it

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.3Ask turing about that other one also

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok I hope to see you around again. Enjoy

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0@mertsj, yes, well, done @Jinnie: do you know L'hospital's rule? derivative of top and bottom gives \[\frac{9\cos(9x)}{1}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hey turningtest thats my first time hearing about that rule

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0can you take the derivative of sin(9x) ?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0Then you can't use L'hospital, which unfortunately means I can't help you as well as I hoped. I can tell you that \[\lim_{x \rightarrow 0}\frac{\sin x}{x}=1\]but proof of that are bit complicated without L'hospital's rule. All I can suggest is to try to use that fact to help you. anyway the answer is that the limit in your question is 9

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok, would you be willing to do several more of these and I ask my professor about this rule next class?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0have you learned derivatives yet at all?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nah we just started school last week

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0dw:1326948473758:dw lim as x approaches 0. this is all i need help with

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0then all I can do is give answers without explanation, because the way I solve these is with a method you don't know. If you just want the answer I refer you to wolfram alpha as mertsj did. Here is your question posted there: http://www.wolframalpha.com/input/?i=limit+x+to+0+sin%289x%29%2Fx learn to use this site, but it will not help you understand, so don't rely on it.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.0this last one is 1/3 try typing it into wolfram to see if I'm right

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0alright thanks for the help

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0im done thanks to all

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0good night hope to see everyone again
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