limit and absolute absolute value problem
$begingroup$
$$lim_{x to -2} frac{2-|x|}{2+x}$$
If I calculate the left and right-hand limit I get different results.
Left hand side:
$$lim_{x to -2^-}frac{2+x}{2+x}=1$$
Right hand side: $$lim_{x to -2^+} frac{2-x}{2+x}=text{undefined}$$
My question is that my procedure is right or wrong?
real-analysis limits absolute-value
$endgroup$
add a comment |
$begingroup$
$$lim_{x to -2} frac{2-|x|}{2+x}$$
If I calculate the left and right-hand limit I get different results.
Left hand side:
$$lim_{x to -2^-}frac{2+x}{2+x}=1$$
Right hand side: $$lim_{x to -2^+} frac{2-x}{2+x}=text{undefined}$$
My question is that my procedure is right or wrong?
real-analysis limits absolute-value
$endgroup$
$begingroup$
I get a solution from an unauthorized source what explains that it is 1
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
Note that the modulus function is not continuous at $0$, but it is around a neighborhood of $-2$, hence you could compute the limit simply assuming $|x|=-x$.
$endgroup$
– Mefitico
5 hours ago
add a comment |
$begingroup$
$$lim_{x to -2} frac{2-|x|}{2+x}$$
If I calculate the left and right-hand limit I get different results.
Left hand side:
$$lim_{x to -2^-}frac{2+x}{2+x}=1$$
Right hand side: $$lim_{x to -2^+} frac{2-x}{2+x}=text{undefined}$$
My question is that my procedure is right or wrong?
real-analysis limits absolute-value
$endgroup$
$$lim_{x to -2} frac{2-|x|}{2+x}$$
If I calculate the left and right-hand limit I get different results.
Left hand side:
$$lim_{x to -2^-}frac{2+x}{2+x}=1$$
Right hand side: $$lim_{x to -2^+} frac{2-x}{2+x}=text{undefined}$$
My question is that my procedure is right or wrong?
real-analysis limits absolute-value
real-analysis limits absolute-value
edited 8 hours ago
Mutantoe
610513
610513
asked 16 hours ago
Jobiar HossainJobiar Hossain
363
363
$begingroup$
I get a solution from an unauthorized source what explains that it is 1
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
Note that the modulus function is not continuous at $0$, but it is around a neighborhood of $-2$, hence you could compute the limit simply assuming $|x|=-x$.
$endgroup$
– Mefitico
5 hours ago
add a comment |
$begingroup$
I get a solution from an unauthorized source what explains that it is 1
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
Note that the modulus function is not continuous at $0$, but it is around a neighborhood of $-2$, hence you could compute the limit simply assuming $|x|=-x$.
$endgroup$
– Mefitico
5 hours ago
$begingroup$
I get a solution from an unauthorized source what explains that it is 1
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
I get a solution from an unauthorized source what explains that it is 1
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
Note that the modulus function is not continuous at $0$, but it is around a neighborhood of $-2$, hence you could compute the limit simply assuming $|x|=-x$.
$endgroup$
– Mefitico
5 hours ago
$begingroup$
Note that the modulus function is not continuous at $0$, but it is around a neighborhood of $-2$, hence you could compute the limit simply assuming $|x|=-x$.
$endgroup$
– Mefitico
5 hours ago
add a comment |
5 Answers
5
active
oldest
votes
$begingroup$
Since $x to -2$, we can assume that $x < 0$ so that $|x| = -x$.
Then $$frac{2-|x|}{2+x} = frac{2+x}{2+x} = 1 xrightarrow{x to -2} 1$$
so the limit exists and it is equal to $1$.
$endgroup$
add a comment |
$begingroup$
When $x$ is near $-2$ approaching it from the left, $2+x$ is equivalent to $2-|x|$ (if $x<0$, then $x=-|x|$):
$$
lim_{xto-2^-}frac{2-|x|}{2+x}=lim_{xto-2^-}frac{2-|x|}{2-|x|}=lim_{xto-2^-}1=1.
$$
When $x$ is near $-2$ approaching it from the right, $2+x$ also seems to be equivalent to $2-|x|$:
$$
lim_{xto-2^+}frac{2-|x|}{2+x}=lim_{xto-2^+}frac{2-|x|}{2-|x|}=lim_{xto-2^+}1=1.
$$
Since both one-sided limits are equal to the same number, the limit exists and is equal to $1$:
$$lim_{xto-2}frac{2-|x|}{2+x}=1.$$
Even though the function itself is undefined at $x=-2$ because the denominator at that point is zero ($f(-2)=frac{2-|-2|}{2-2}=frac{0}{0}$), the limit of this function at $x=-2$ does exist and is equal to $1$.
$endgroup$
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
1
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
add a comment |
$begingroup$
Multiply and divide by $2+|x|$ and cancel:
$$lim_{x to -2} frac{2-|x|}{2+x}=lim_{x to -2} frac{4-x^2}{(2+x)(2+|x|)}=lim_{x to -2} frac{2-x}{2+|x|}=frac{2-(-2)}{2+2}=1.$$
$endgroup$
add a comment |
$begingroup$
$$lim_{xrightarrow-2}frac{2-|x|}{2+x}=lim_{xrightarrow-2}frac{2+x}{2+x}=1.$$
$endgroup$
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
|
show 2 more comments
$begingroup$
What about L'Hospital's Rule?
Since
$$frac{2-|-2|}{2+-2}=frac{0}{0}$$
then
$$frac{d}{dx}(2-|x|)=-frac{x}{|x|}, frac{d}{dx}(2+x)=1$$
evaluate
$frac{-frac{x}{|x|}}{1}$
at $x=-2$
yields
$$frac{-frac{-2}{|-2|}}{1} = frac{-(-1)}{1}=1$$
New contributor
$endgroup$
add a comment |
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5 Answers
5
active
oldest
votes
5 Answers
5
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Since $x to -2$, we can assume that $x < 0$ so that $|x| = -x$.
Then $$frac{2-|x|}{2+x} = frac{2+x}{2+x} = 1 xrightarrow{x to -2} 1$$
so the limit exists and it is equal to $1$.
$endgroup$
add a comment |
$begingroup$
Since $x to -2$, we can assume that $x < 0$ so that $|x| = -x$.
Then $$frac{2-|x|}{2+x} = frac{2+x}{2+x} = 1 xrightarrow{x to -2} 1$$
so the limit exists and it is equal to $1$.
$endgroup$
add a comment |
$begingroup$
Since $x to -2$, we can assume that $x < 0$ so that $|x| = -x$.
Then $$frac{2-|x|}{2+x} = frac{2+x}{2+x} = 1 xrightarrow{x to -2} 1$$
so the limit exists and it is equal to $1$.
$endgroup$
Since $x to -2$, we can assume that $x < 0$ so that $|x| = -x$.
Then $$frac{2-|x|}{2+x} = frac{2+x}{2+x} = 1 xrightarrow{x to -2} 1$$
so the limit exists and it is equal to $1$.
answered 13 hours ago
mechanodroidmechanodroid
27.5k62446
27.5k62446
add a comment |
add a comment |
$begingroup$
When $x$ is near $-2$ approaching it from the left, $2+x$ is equivalent to $2-|x|$ (if $x<0$, then $x=-|x|$):
$$
lim_{xto-2^-}frac{2-|x|}{2+x}=lim_{xto-2^-}frac{2-|x|}{2-|x|}=lim_{xto-2^-}1=1.
$$
When $x$ is near $-2$ approaching it from the right, $2+x$ also seems to be equivalent to $2-|x|$:
$$
lim_{xto-2^+}frac{2-|x|}{2+x}=lim_{xto-2^+}frac{2-|x|}{2-|x|}=lim_{xto-2^+}1=1.
$$
Since both one-sided limits are equal to the same number, the limit exists and is equal to $1$:
$$lim_{xto-2}frac{2-|x|}{2+x}=1.$$
Even though the function itself is undefined at $x=-2$ because the denominator at that point is zero ($f(-2)=frac{2-|-2|}{2-2}=frac{0}{0}$), the limit of this function at $x=-2$ does exist and is equal to $1$.
$endgroup$
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
1
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
add a comment |
$begingroup$
When $x$ is near $-2$ approaching it from the left, $2+x$ is equivalent to $2-|x|$ (if $x<0$, then $x=-|x|$):
$$
lim_{xto-2^-}frac{2-|x|}{2+x}=lim_{xto-2^-}frac{2-|x|}{2-|x|}=lim_{xto-2^-}1=1.
$$
When $x$ is near $-2$ approaching it from the right, $2+x$ also seems to be equivalent to $2-|x|$:
$$
lim_{xto-2^+}frac{2-|x|}{2+x}=lim_{xto-2^+}frac{2-|x|}{2-|x|}=lim_{xto-2^+}1=1.
$$
Since both one-sided limits are equal to the same number, the limit exists and is equal to $1$:
$$lim_{xto-2}frac{2-|x|}{2+x}=1.$$
Even though the function itself is undefined at $x=-2$ because the denominator at that point is zero ($f(-2)=frac{2-|-2|}{2-2}=frac{0}{0}$), the limit of this function at $x=-2$ does exist and is equal to $1$.
$endgroup$
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
1
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
add a comment |
$begingroup$
When $x$ is near $-2$ approaching it from the left, $2+x$ is equivalent to $2-|x|$ (if $x<0$, then $x=-|x|$):
$$
lim_{xto-2^-}frac{2-|x|}{2+x}=lim_{xto-2^-}frac{2-|x|}{2-|x|}=lim_{xto-2^-}1=1.
$$
When $x$ is near $-2$ approaching it from the right, $2+x$ also seems to be equivalent to $2-|x|$:
$$
lim_{xto-2^+}frac{2-|x|}{2+x}=lim_{xto-2^+}frac{2-|x|}{2-|x|}=lim_{xto-2^+}1=1.
$$
Since both one-sided limits are equal to the same number, the limit exists and is equal to $1$:
$$lim_{xto-2}frac{2-|x|}{2+x}=1.$$
Even though the function itself is undefined at $x=-2$ because the denominator at that point is zero ($f(-2)=frac{2-|-2|}{2-2}=frac{0}{0}$), the limit of this function at $x=-2$ does exist and is equal to $1$.
$endgroup$
When $x$ is near $-2$ approaching it from the left, $2+x$ is equivalent to $2-|x|$ (if $x<0$, then $x=-|x|$):
$$
lim_{xto-2^-}frac{2-|x|}{2+x}=lim_{xto-2^-}frac{2-|x|}{2-|x|}=lim_{xto-2^-}1=1.
$$
When $x$ is near $-2$ approaching it from the right, $2+x$ also seems to be equivalent to $2-|x|$:
$$
lim_{xto-2^+}frac{2-|x|}{2+x}=lim_{xto-2^+}frac{2-|x|}{2-|x|}=lim_{xto-2^+}1=1.
$$
Since both one-sided limits are equal to the same number, the limit exists and is equal to $1$:
$$lim_{xto-2}frac{2-|x|}{2+x}=1.$$
Even though the function itself is undefined at $x=-2$ because the denominator at that point is zero ($f(-2)=frac{2-|-2|}{2-2}=frac{0}{0}$), the limit of this function at $x=-2$ does exist and is equal to $1$.
edited 5 hours ago
answered 16 hours ago
Mike R.Mike R.
2,025314
2,025314
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
1
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
add a comment |
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
1
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
$begingroup$
When x is near −2 approaching it from the right, 2+x also seems to be equivalent to 2−|x| ...sorry, I don't get it
$endgroup$
– Jobiar Hossain
15 hours ago
1
1
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
$begingroup$
I get it. you are amazing to explain
$endgroup$
– Jobiar Hossain
15 hours ago
add a comment |
$begingroup$
Multiply and divide by $2+|x|$ and cancel:
$$lim_{x to -2} frac{2-|x|}{2+x}=lim_{x to -2} frac{4-x^2}{(2+x)(2+|x|)}=lim_{x to -2} frac{2-x}{2+|x|}=frac{2-(-2)}{2+2}=1.$$
$endgroup$
add a comment |
$begingroup$
Multiply and divide by $2+|x|$ and cancel:
$$lim_{x to -2} frac{2-|x|}{2+x}=lim_{x to -2} frac{4-x^2}{(2+x)(2+|x|)}=lim_{x to -2} frac{2-x}{2+|x|}=frac{2-(-2)}{2+2}=1.$$
$endgroup$
add a comment |
$begingroup$
Multiply and divide by $2+|x|$ and cancel:
$$lim_{x to -2} frac{2-|x|}{2+x}=lim_{x to -2} frac{4-x^2}{(2+x)(2+|x|)}=lim_{x to -2} frac{2-x}{2+|x|}=frac{2-(-2)}{2+2}=1.$$
$endgroup$
Multiply and divide by $2+|x|$ and cancel:
$$lim_{x to -2} frac{2-|x|}{2+x}=lim_{x to -2} frac{4-x^2}{(2+x)(2+|x|)}=lim_{x to -2} frac{2-x}{2+|x|}=frac{2-(-2)}{2+2}=1.$$
answered 13 hours ago
farruhotafarruhota
20.2k2738
20.2k2738
add a comment |
add a comment |
$begingroup$
$$lim_{xrightarrow-2}frac{2-|x|}{2+x}=lim_{xrightarrow-2}frac{2+x}{2+x}=1.$$
$endgroup$
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
|
show 2 more comments
$begingroup$
$$lim_{xrightarrow-2}frac{2-|x|}{2+x}=lim_{xrightarrow-2}frac{2+x}{2+x}=1.$$
$endgroup$
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
|
show 2 more comments
$begingroup$
$$lim_{xrightarrow-2}frac{2-|x|}{2+x}=lim_{xrightarrow-2}frac{2+x}{2+x}=1.$$
$endgroup$
$$lim_{xrightarrow-2}frac{2-|x|}{2+x}=lim_{xrightarrow-2}frac{2+x}{2+x}=1.$$
answered 16 hours ago
Michael RozenbergMichael Rozenberg
103k1891195
103k1891195
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
|
show 2 more comments
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
it occurs when you consider right hand side limit I mean x if x>0 and Left hand side limit -x if x<0
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
@Jobiar Hossain Since $xrightarrow-2$, we can assume that $x<0$ because for $xgeq0$ it's not interesting.
$endgroup$
– Michael Rozenberg
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
yes, but why do we not consider left hand side and right hand side limit ? I know this idea but it don't give information about left hand side limit and right hand side limit.
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
@Jobiar Hossain $xrightarrow-2$. Id est, it's interesting what happens around $-2$, id est, for $x<0$. If $xrightarrow-2$ so can be $x>-2$ and can be $x<-2$ by the definition of the limits. We don't need to consider two cases here.
$endgroup$
– Michael Rozenberg
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
$begingroup$
If you draw the graph, you will find that there is a vertical Asymptote at x=-2
$endgroup$
– Jobiar Hossain
15 hours ago
|
show 2 more comments
$begingroup$
What about L'Hospital's Rule?
Since
$$frac{2-|-2|}{2+-2}=frac{0}{0}$$
then
$$frac{d}{dx}(2-|x|)=-frac{x}{|x|}, frac{d}{dx}(2+x)=1$$
evaluate
$frac{-frac{x}{|x|}}{1}$
at $x=-2$
yields
$$frac{-frac{-2}{|-2|}}{1} = frac{-(-1)}{1}=1$$
New contributor
$endgroup$
add a comment |
$begingroup$
What about L'Hospital's Rule?
Since
$$frac{2-|-2|}{2+-2}=frac{0}{0}$$
then
$$frac{d}{dx}(2-|x|)=-frac{x}{|x|}, frac{d}{dx}(2+x)=1$$
evaluate
$frac{-frac{x}{|x|}}{1}$
at $x=-2$
yields
$$frac{-frac{-2}{|-2|}}{1} = frac{-(-1)}{1}=1$$
New contributor
$endgroup$
add a comment |
$begingroup$
What about L'Hospital's Rule?
Since
$$frac{2-|-2|}{2+-2}=frac{0}{0}$$
then
$$frac{d}{dx}(2-|x|)=-frac{x}{|x|}, frac{d}{dx}(2+x)=1$$
evaluate
$frac{-frac{x}{|x|}}{1}$
at $x=-2$
yields
$$frac{-frac{-2}{|-2|}}{1} = frac{-(-1)}{1}=1$$
New contributor
$endgroup$
What about L'Hospital's Rule?
Since
$$frac{2-|-2|}{2+-2}=frac{0}{0}$$
then
$$frac{d}{dx}(2-|x|)=-frac{x}{|x|}, frac{d}{dx}(2+x)=1$$
evaluate
$frac{-frac{x}{|x|}}{1}$
at $x=-2$
yields
$$frac{-frac{-2}{|-2|}}{1} = frac{-(-1)}{1}=1$$
New contributor
New contributor
answered 5 hours ago
chiliNUTchiliNUT
1113
1113
New contributor
New contributor
add a comment |
add a comment |
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$begingroup$
I get a solution from an unauthorized source what explains that it is 1
$endgroup$
– Jobiar Hossain
16 hours ago
$begingroup$
Note that the modulus function is not continuous at $0$, but it is around a neighborhood of $-2$, hence you could compute the limit simply assuming $|x|=-x$.
$endgroup$
– Mefitico
5 hours ago