Evaluating the limit $lim_{x to infty}left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)$
I wanna know how to do this limit
$lim_{x to infty}left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)$
calculus limits infinity
add a comment |
I wanna know how to do this limit
$lim_{x to infty}left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)$
calculus limits infinity
Try multiplying and dividing by the conjugate root to eliminate the roots.
– D.B.
Nov 22 at 4:37
thats what i did, but i got stuck
– Franco Cabrera
Nov 22 at 4:41
math.stackexchange.com/questions/2959619/…
– lab bhattacharjee
Nov 22 at 4:41
Remember that intuitively, when you work with limits of polynomials, you can often just replace the polynomial with it's leading term and get the right answer. In this case you get $0$
– Ovi
Nov 22 at 4:49
add a comment |
I wanna know how to do this limit
$lim_{x to infty}left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)$
calculus limits infinity
I wanna know how to do this limit
$lim_{x to infty}left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)$
calculus limits infinity
calculus limits infinity
edited Nov 22 at 4:37
asked Nov 22 at 4:32
Franco Cabrera
64
64
Try multiplying and dividing by the conjugate root to eliminate the roots.
– D.B.
Nov 22 at 4:37
thats what i did, but i got stuck
– Franco Cabrera
Nov 22 at 4:41
math.stackexchange.com/questions/2959619/…
– lab bhattacharjee
Nov 22 at 4:41
Remember that intuitively, when you work with limits of polynomials, you can often just replace the polynomial with it's leading term and get the right answer. In this case you get $0$
– Ovi
Nov 22 at 4:49
add a comment |
Try multiplying and dividing by the conjugate root to eliminate the roots.
– D.B.
Nov 22 at 4:37
thats what i did, but i got stuck
– Franco Cabrera
Nov 22 at 4:41
math.stackexchange.com/questions/2959619/…
– lab bhattacharjee
Nov 22 at 4:41
Remember that intuitively, when you work with limits of polynomials, you can often just replace the polynomial with it's leading term and get the right answer. In this case you get $0$
– Ovi
Nov 22 at 4:49
Try multiplying and dividing by the conjugate root to eliminate the roots.
– D.B.
Nov 22 at 4:37
Try multiplying and dividing by the conjugate root to eliminate the roots.
– D.B.
Nov 22 at 4:37
thats what i did, but i got stuck
– Franco Cabrera
Nov 22 at 4:41
thats what i did, but i got stuck
– Franco Cabrera
Nov 22 at 4:41
math.stackexchange.com/questions/2959619/…
– lab bhattacharjee
Nov 22 at 4:41
math.stackexchange.com/questions/2959619/…
– lab bhattacharjee
Nov 22 at 4:41
Remember that intuitively, when you work with limits of polynomials, you can often just replace the polynomial with it's leading term and get the right answer. In this case you get $0$
– Ovi
Nov 22 at 4:49
Remember that intuitively, when you work with limits of polynomials, you can often just replace the polynomial with it's leading term and get the right answer. In this case you get $0$
– Ovi
Nov 22 at 4:49
add a comment |
3 Answers
3
active
oldest
votes
First of all, rationalise the expression by multiplying numerator and denominator by$displaystyle sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}$
begin{equation*}
end{equation*}
We get
begin{gather*}
lim xrightarrow infty frac{-x^{3} -15x^{2} +6}{sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}}\
end{gather*}
Divide numerator and denominator by $displaystyle x^{2}$
begin{equation*}
lim xrightarrow infty frac{-x-15+frac{6}{x^{2}}}{sqrt{1-frac{1}{x} +frac{1}{x^{4}}} +sqrt{1+frac{15}{x^{2}} -frac{5}{x^{4}}}}
end{equation*}
Clearly the given expression tends to$displaystyle -infty $ as $displaystyle xrightarrow infty $
begin{equation*}
end{equation*}
add a comment |
You should multiply by the conjugate of the expression, then proceed.
begin{align}
frac{left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}\
end{align}
begin{align}
frac{(x^4 -x^3+1)-(x^4+15x^2-5)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}
end{align}
Operate and calculate the limit.
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
|
show 3 more comments
Another manipulation:
Let $a,b >0$, real.
$a-b=(√a-√b)(√a+√b)$, then
$√a-√b = dfrac{a-b}{√a+√b}.$
$a: = (x^4-x^3+1)^{1/2},$
$b=(x^4+15x^2-5)^{1/2}.$
$small{f(x):=}$
$small {=dfrac{-x^3-15x^2+6}{(x^4-x^3+1)^{1/2}+(x^4+15x^2-5)^{1/2}}}$
Note : For large x (positive) the numerator is negative, the denominator positive: Increasing the denominator makes the fraction bigger.
Hence
$f(x) lt $
$dfrac{-x^3+6}{(x^4+1)^{1/2}+(x^4+15x^2)^{1/2}} lt $
$dfrac{-x^3+6}{√2x^2+√2x^2}=$
$dfrac{-x^3+6}{(2√2)x^2}.$
Take the limit.
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3008741%2fevaluating-the-limit-lim-x-to-infty-left-sqrtx4-x31-sqrtx415x2%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
First of all, rationalise the expression by multiplying numerator and denominator by$displaystyle sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}$
begin{equation*}
end{equation*}
We get
begin{gather*}
lim xrightarrow infty frac{-x^{3} -15x^{2} +6}{sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}}\
end{gather*}
Divide numerator and denominator by $displaystyle x^{2}$
begin{equation*}
lim xrightarrow infty frac{-x-15+frac{6}{x^{2}}}{sqrt{1-frac{1}{x} +frac{1}{x^{4}}} +sqrt{1+frac{15}{x^{2}} -frac{5}{x^{4}}}}
end{equation*}
Clearly the given expression tends to$displaystyle -infty $ as $displaystyle xrightarrow infty $
begin{equation*}
end{equation*}
add a comment |
First of all, rationalise the expression by multiplying numerator and denominator by$displaystyle sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}$
begin{equation*}
end{equation*}
We get
begin{gather*}
lim xrightarrow infty frac{-x^{3} -15x^{2} +6}{sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}}\
end{gather*}
Divide numerator and denominator by $displaystyle x^{2}$
begin{equation*}
lim xrightarrow infty frac{-x-15+frac{6}{x^{2}}}{sqrt{1-frac{1}{x} +frac{1}{x^{4}}} +sqrt{1+frac{15}{x^{2}} -frac{5}{x^{4}}}}
end{equation*}
Clearly the given expression tends to$displaystyle -infty $ as $displaystyle xrightarrow infty $
begin{equation*}
end{equation*}
add a comment |
First of all, rationalise the expression by multiplying numerator and denominator by$displaystyle sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}$
begin{equation*}
end{equation*}
We get
begin{gather*}
lim xrightarrow infty frac{-x^{3} -15x^{2} +6}{sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}}\
end{gather*}
Divide numerator and denominator by $displaystyle x^{2}$
begin{equation*}
lim xrightarrow infty frac{-x-15+frac{6}{x^{2}}}{sqrt{1-frac{1}{x} +frac{1}{x^{4}}} +sqrt{1+frac{15}{x^{2}} -frac{5}{x^{4}}}}
end{equation*}
Clearly the given expression tends to$displaystyle -infty $ as $displaystyle xrightarrow infty $
begin{equation*}
end{equation*}
First of all, rationalise the expression by multiplying numerator and denominator by$displaystyle sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}$
begin{equation*}
end{equation*}
We get
begin{gather*}
lim xrightarrow infty frac{-x^{3} -15x^{2} +6}{sqrt{x^{4} -x^{3} +1} + sqrt{x^{4} +15x^{2} -5}}\
end{gather*}
Divide numerator and denominator by $displaystyle x^{2}$
begin{equation*}
lim xrightarrow infty frac{-x-15+frac{6}{x^{2}}}{sqrt{1-frac{1}{x} +frac{1}{x^{4}}} +sqrt{1+frac{15}{x^{2}} -frac{5}{x^{4}}}}
end{equation*}
Clearly the given expression tends to$displaystyle -infty $ as $displaystyle xrightarrow infty $
begin{equation*}
end{equation*}
answered Nov 22 at 5:49
Dikshit Gautam
795
795
add a comment |
add a comment |
You should multiply by the conjugate of the expression, then proceed.
begin{align}
frac{left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}\
end{align}
begin{align}
frac{(x^4 -x^3+1)-(x^4+15x^2-5)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}
end{align}
Operate and calculate the limit.
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
|
show 3 more comments
You should multiply by the conjugate of the expression, then proceed.
begin{align}
frac{left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}\
end{align}
begin{align}
frac{(x^4 -x^3+1)-(x^4+15x^2-5)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}
end{align}
Operate and calculate the limit.
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
|
show 3 more comments
You should multiply by the conjugate of the expression, then proceed.
begin{align}
frac{left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}\
end{align}
begin{align}
frac{(x^4 -x^3+1)-(x^4+15x^2-5)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}
end{align}
Operate and calculate the limit.
You should multiply by the conjugate of the expression, then proceed.
begin{align}
frac{left(sqrt{x^4 -x^3+1}-sqrt{x^4+15x^2-5},right)left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}\
end{align}
begin{align}
frac{(x^4 -x^3+1)-(x^4+15x^2-5)}{left(sqrt{x^4 -x^3+1}+sqrt{x^4+15x^2-5},right)}
end{align}
Operate and calculate the limit.
edited Nov 22 at 6:03
b00n heT
10.2k12134
10.2k12134
answered Nov 22 at 4:48
Alberto Torrejon Valenzuela
276
276
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
|
show 3 more comments
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
negative! that's cool!
– Christopher Marley
Nov 22 at 4:52
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
What does that mean? Sorry I`m not a fully native english speaker so those two words in the same sentence make me confuse.
– Alberto Torrejon Valenzuela
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
and then, should i evaluate de sign of de function to see the lateral limits?
– Franco Cabrera
Nov 22 at 4:54
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
No need if you just want to give a result of the limit. If you want to study the function then I suppose you should
– Alberto Torrejon Valenzuela
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
Alberto, despues de eso tendria que evaluar el signo de f? ver si los limites laterales son iguales y obtener su valor?
– Franco Cabrera
Nov 22 at 4:56
|
show 3 more comments
Another manipulation:
Let $a,b >0$, real.
$a-b=(√a-√b)(√a+√b)$, then
$√a-√b = dfrac{a-b}{√a+√b}.$
$a: = (x^4-x^3+1)^{1/2},$
$b=(x^4+15x^2-5)^{1/2}.$
$small{f(x):=}$
$small {=dfrac{-x^3-15x^2+6}{(x^4-x^3+1)^{1/2}+(x^4+15x^2-5)^{1/2}}}$
Note : For large x (positive) the numerator is negative, the denominator positive: Increasing the denominator makes the fraction bigger.
Hence
$f(x) lt $
$dfrac{-x^3+6}{(x^4+1)^{1/2}+(x^4+15x^2)^{1/2}} lt $
$dfrac{-x^3+6}{√2x^2+√2x^2}=$
$dfrac{-x^3+6}{(2√2)x^2}.$
Take the limit.
add a comment |
Another manipulation:
Let $a,b >0$, real.
$a-b=(√a-√b)(√a+√b)$, then
$√a-√b = dfrac{a-b}{√a+√b}.$
$a: = (x^4-x^3+1)^{1/2},$
$b=(x^4+15x^2-5)^{1/2}.$
$small{f(x):=}$
$small {=dfrac{-x^3-15x^2+6}{(x^4-x^3+1)^{1/2}+(x^4+15x^2-5)^{1/2}}}$
Note : For large x (positive) the numerator is negative, the denominator positive: Increasing the denominator makes the fraction bigger.
Hence
$f(x) lt $
$dfrac{-x^3+6}{(x^4+1)^{1/2}+(x^4+15x^2)^{1/2}} lt $
$dfrac{-x^3+6}{√2x^2+√2x^2}=$
$dfrac{-x^3+6}{(2√2)x^2}.$
Take the limit.
add a comment |
Another manipulation:
Let $a,b >0$, real.
$a-b=(√a-√b)(√a+√b)$, then
$√a-√b = dfrac{a-b}{√a+√b}.$
$a: = (x^4-x^3+1)^{1/2},$
$b=(x^4+15x^2-5)^{1/2}.$
$small{f(x):=}$
$small {=dfrac{-x^3-15x^2+6}{(x^4-x^3+1)^{1/2}+(x^4+15x^2-5)^{1/2}}}$
Note : For large x (positive) the numerator is negative, the denominator positive: Increasing the denominator makes the fraction bigger.
Hence
$f(x) lt $
$dfrac{-x^3+6}{(x^4+1)^{1/2}+(x^4+15x^2)^{1/2}} lt $
$dfrac{-x^3+6}{√2x^2+√2x^2}=$
$dfrac{-x^3+6}{(2√2)x^2}.$
Take the limit.
Another manipulation:
Let $a,b >0$, real.
$a-b=(√a-√b)(√a+√b)$, then
$√a-√b = dfrac{a-b}{√a+√b}.$
$a: = (x^4-x^3+1)^{1/2},$
$b=(x^4+15x^2-5)^{1/2}.$
$small{f(x):=}$
$small {=dfrac{-x^3-15x^2+6}{(x^4-x^3+1)^{1/2}+(x^4+15x^2-5)^{1/2}}}$
Note : For large x (positive) the numerator is negative, the denominator positive: Increasing the denominator makes the fraction bigger.
Hence
$f(x) lt $
$dfrac{-x^3+6}{(x^4+1)^{1/2}+(x^4+15x^2)^{1/2}} lt $
$dfrac{-x^3+6}{√2x^2+√2x^2}=$
$dfrac{-x^3+6}{(2√2)x^2}.$
Take the limit.
edited Nov 22 at 9:44
answered Nov 22 at 9:34
Peter Szilas
10.6k2720
10.6k2720
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3008741%2fevaluating-the-limit-lim-x-to-infty-left-sqrtx4-x31-sqrtx415x2%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Try multiplying and dividing by the conjugate root to eliminate the roots.
– D.B.
Nov 22 at 4:37
thats what i did, but i got stuck
– Franco Cabrera
Nov 22 at 4:41
math.stackexchange.com/questions/2959619/…
– lab bhattacharjee
Nov 22 at 4:41
Remember that intuitively, when you work with limits of polynomials, you can often just replace the polynomial with it's leading term and get the right answer. In this case you get $0$
– Ovi
Nov 22 at 4:49