explain why ${left(frac{{1}}{{2}}right)}^{infty}=0$
$begingroup$
Mathematica shows
${left(frac{{1}}{{2}}right)}^{infty}=0$, anyone can explain why ?
I know we can get $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}={0}$ by taking limit , does ${left(frac{{1}}{{2}}right)}^{infty}$ is just an abbreviated expression of $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}$
P.S. $infty = +infty$ here.
calculus limits nonstandard-analysis
$endgroup$
|
show 3 more comments
$begingroup$
Mathematica shows
${left(frac{{1}}{{2}}right)}^{infty}=0$, anyone can explain why ?
I know we can get $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}={0}$ by taking limit , does ${left(frac{{1}}{{2}}right)}^{infty}$ is just an abbreviated expression of $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}$
P.S. $infty = +infty$ here.
calculus limits nonstandard-analysis
$endgroup$
2
$begingroup$
Yes. (words to fill the comment)
$endgroup$
– Vinícius Novelli
May 3 '15 at 7:48
$begingroup$
As long as you agree that $infty = +infty$. I personally don't, and in calculus I usually teach that $infty$ means nothing. But Mathematica agrees with this shorthand.
$endgroup$
– Siminore
May 3 '15 at 7:50
$begingroup$
Well exactly infinity would not be defined, because it's a concept not a number. However, the notation that $lim_{xto infty}$ implies that $x$ is approaching infinity. If you directly say that it's an abbreviation, it won't be a good idea. It's the limit as $x$ approaches it.
$endgroup$
– Mann
May 3 '15 at 7:51
$begingroup$
@Siminore yes, $infty = +infty$ here. I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:55
$begingroup$
@Mann I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:58
|
show 3 more comments
$begingroup$
Mathematica shows
${left(frac{{1}}{{2}}right)}^{infty}=0$, anyone can explain why ?
I know we can get $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}={0}$ by taking limit , does ${left(frac{{1}}{{2}}right)}^{infty}$ is just an abbreviated expression of $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}$
P.S. $infty = +infty$ here.
calculus limits nonstandard-analysis
$endgroup$
Mathematica shows
${left(frac{{1}}{{2}}right)}^{infty}=0$, anyone can explain why ?
I know we can get $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}={0}$ by taking limit , does ${left(frac{{1}}{{2}}right)}^{infty}$ is just an abbreviated expression of $limlimits_{{{x}toinfty}}{left(frac{{1}}{{2}}right)}^{{x}}$
P.S. $infty = +infty$ here.
calculus limits nonstandard-analysis
calculus limits nonstandard-analysis
edited May 3 '15 at 8:40
Francesco Gramano
1476
1476
asked May 3 '15 at 7:46
iMathiMath
1,006821
1,006821
2
$begingroup$
Yes. (words to fill the comment)
$endgroup$
– Vinícius Novelli
May 3 '15 at 7:48
$begingroup$
As long as you agree that $infty = +infty$. I personally don't, and in calculus I usually teach that $infty$ means nothing. But Mathematica agrees with this shorthand.
$endgroup$
– Siminore
May 3 '15 at 7:50
$begingroup$
Well exactly infinity would not be defined, because it's a concept not a number. However, the notation that $lim_{xto infty}$ implies that $x$ is approaching infinity. If you directly say that it's an abbreviation, it won't be a good idea. It's the limit as $x$ approaches it.
$endgroup$
– Mann
May 3 '15 at 7:51
$begingroup$
@Siminore yes, $infty = +infty$ here. I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:55
$begingroup$
@Mann I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:58
|
show 3 more comments
2
$begingroup$
Yes. (words to fill the comment)
$endgroup$
– Vinícius Novelli
May 3 '15 at 7:48
$begingroup$
As long as you agree that $infty = +infty$. I personally don't, and in calculus I usually teach that $infty$ means nothing. But Mathematica agrees with this shorthand.
$endgroup$
– Siminore
May 3 '15 at 7:50
$begingroup$
Well exactly infinity would not be defined, because it's a concept not a number. However, the notation that $lim_{xto infty}$ implies that $x$ is approaching infinity. If you directly say that it's an abbreviation, it won't be a good idea. It's the limit as $x$ approaches it.
$endgroup$
– Mann
May 3 '15 at 7:51
$begingroup$
@Siminore yes, $infty = +infty$ here. I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:55
$begingroup$
@Mann I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:58
2
2
$begingroup$
Yes. (words to fill the comment)
$endgroup$
– Vinícius Novelli
May 3 '15 at 7:48
$begingroup$
Yes. (words to fill the comment)
$endgroup$
– Vinícius Novelli
May 3 '15 at 7:48
$begingroup$
As long as you agree that $infty = +infty$. I personally don't, and in calculus I usually teach that $infty$ means nothing. But Mathematica agrees with this shorthand.
$endgroup$
– Siminore
May 3 '15 at 7:50
$begingroup$
As long as you agree that $infty = +infty$. I personally don't, and in calculus I usually teach that $infty$ means nothing. But Mathematica agrees with this shorthand.
$endgroup$
– Siminore
May 3 '15 at 7:50
$begingroup$
Well exactly infinity would not be defined, because it's a concept not a number. However, the notation that $lim_{xto infty}$ implies that $x$ is approaching infinity. If you directly say that it's an abbreviation, it won't be a good idea. It's the limit as $x$ approaches it.
$endgroup$
– Mann
May 3 '15 at 7:51
$begingroup$
Well exactly infinity would not be defined, because it's a concept not a number. However, the notation that $lim_{xto infty}$ implies that $x$ is approaching infinity. If you directly say that it's an abbreviation, it won't be a good idea. It's the limit as $x$ approaches it.
$endgroup$
– Mann
May 3 '15 at 7:51
$begingroup$
@Siminore yes, $infty = +infty$ here. I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:55
$begingroup$
@Siminore yes, $infty = +infty$ here. I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:55
$begingroup$
@Mann I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:58
$begingroup$
@Mann I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:58
|
show 3 more comments
3 Answers
3
active
oldest
votes
$begingroup$
$(1/2)^2=1/4$ and $(1/2)^{10}=1/1024$ and then $(1/2)^{20}=1/1048576$. As the power gets larger, the denominator approaches infinity. This makes the value of the fraction tend to zero.
This might help.
$endgroup$
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
add a comment |
$begingroup$
I think this is just a definition from Wolfram Alpha. As you see here!
If you type in $left(frac{1}{2}right)^infty == limlimits_{x to infty} left(frac{1}{2}right)^x $, then Wolfram Alpha give you the result: True.
$endgroup$
add a comment |
$begingroup$
What you mean is probably $$lim_{xrightarrow infty} {left(frac{1}{2}right)}^{x}$$
A limit can be defined with epsilon and delta. I.e. can we find any number $delta$ for every $epsilon > 0$ which the expression is close enough to.
A variant of this: We can take the binary number $2^{-i}$ for an integer $i$ which is bounded below by 0, because positive numbers are closed under multiplication. We see that we can make the expression smaller than any such binary number, by just making $x$ large enough, say $x = i + 1$. But the binary number system is good enough to express any positive number if enough digits are allowed. Therefore the limit must be 0.
$endgroup$
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
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active
oldest
votes
$begingroup$
$(1/2)^2=1/4$ and $(1/2)^{10}=1/1024$ and then $(1/2)^{20}=1/1048576$. As the power gets larger, the denominator approaches infinity. This makes the value of the fraction tend to zero.
This might help.
$endgroup$
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
add a comment |
$begingroup$
$(1/2)^2=1/4$ and $(1/2)^{10}=1/1024$ and then $(1/2)^{20}=1/1048576$. As the power gets larger, the denominator approaches infinity. This makes the value of the fraction tend to zero.
This might help.
$endgroup$
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
add a comment |
$begingroup$
$(1/2)^2=1/4$ and $(1/2)^{10}=1/1024$ and then $(1/2)^{20}=1/1048576$. As the power gets larger, the denominator approaches infinity. This makes the value of the fraction tend to zero.
This might help.
$endgroup$
$(1/2)^2=1/4$ and $(1/2)^{10}=1/1024$ and then $(1/2)^{20}=1/1048576$. As the power gets larger, the denominator approaches infinity. This makes the value of the fraction tend to zero.
This might help.
answered May 3 '15 at 7:54
Hritik NarayanHritik Narayan
372312
372312
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
add a comment |
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
$begingroup$
I have already known what you said here, but you seems doesn't answered my question
$endgroup$
– iMath
May 3 '15 at 8:06
add a comment |
$begingroup$
I think this is just a definition from Wolfram Alpha. As you see here!
If you type in $left(frac{1}{2}right)^infty == limlimits_{x to infty} left(frac{1}{2}right)^x $, then Wolfram Alpha give you the result: True.
$endgroup$
add a comment |
$begingroup$
I think this is just a definition from Wolfram Alpha. As you see here!
If you type in $left(frac{1}{2}right)^infty == limlimits_{x to infty} left(frac{1}{2}right)^x $, then Wolfram Alpha give you the result: True.
$endgroup$
add a comment |
$begingroup$
I think this is just a definition from Wolfram Alpha. As you see here!
If you type in $left(frac{1}{2}right)^infty == limlimits_{x to infty} left(frac{1}{2}right)^x $, then Wolfram Alpha give you the result: True.
$endgroup$
I think this is just a definition from Wolfram Alpha. As you see here!
If you type in $left(frac{1}{2}right)^infty == limlimits_{x to infty} left(frac{1}{2}right)^x $, then Wolfram Alpha give you the result: True.
answered May 3 '15 at 8:38
aGeraGer
811823
811823
add a comment |
add a comment |
$begingroup$
What you mean is probably $$lim_{xrightarrow infty} {left(frac{1}{2}right)}^{x}$$
A limit can be defined with epsilon and delta. I.e. can we find any number $delta$ for every $epsilon > 0$ which the expression is close enough to.
A variant of this: We can take the binary number $2^{-i}$ for an integer $i$ which is bounded below by 0, because positive numbers are closed under multiplication. We see that we can make the expression smaller than any such binary number, by just making $x$ large enough, say $x = i + 1$. But the binary number system is good enough to express any positive number if enough digits are allowed. Therefore the limit must be 0.
$endgroup$
add a comment |
$begingroup$
What you mean is probably $$lim_{xrightarrow infty} {left(frac{1}{2}right)}^{x}$$
A limit can be defined with epsilon and delta. I.e. can we find any number $delta$ for every $epsilon > 0$ which the expression is close enough to.
A variant of this: We can take the binary number $2^{-i}$ for an integer $i$ which is bounded below by 0, because positive numbers are closed under multiplication. We see that we can make the expression smaller than any such binary number, by just making $x$ large enough, say $x = i + 1$. But the binary number system is good enough to express any positive number if enough digits are allowed. Therefore the limit must be 0.
$endgroup$
add a comment |
$begingroup$
What you mean is probably $$lim_{xrightarrow infty} {left(frac{1}{2}right)}^{x}$$
A limit can be defined with epsilon and delta. I.e. can we find any number $delta$ for every $epsilon > 0$ which the expression is close enough to.
A variant of this: We can take the binary number $2^{-i}$ for an integer $i$ which is bounded below by 0, because positive numbers are closed under multiplication. We see that we can make the expression smaller than any such binary number, by just making $x$ large enough, say $x = i + 1$. But the binary number system is good enough to express any positive number if enough digits are allowed. Therefore the limit must be 0.
$endgroup$
What you mean is probably $$lim_{xrightarrow infty} {left(frac{1}{2}right)}^{x}$$
A limit can be defined with epsilon and delta. I.e. can we find any number $delta$ for every $epsilon > 0$ which the expression is close enough to.
A variant of this: We can take the binary number $2^{-i}$ for an integer $i$ which is bounded below by 0, because positive numbers are closed under multiplication. We see that we can make the expression smaller than any such binary number, by just making $x$ large enough, say $x = i + 1$. But the binary number system is good enough to express any positive number if enough digits are allowed. Therefore the limit must be 0.
answered May 3 '15 at 9:05
mathreadlermathreadler
14.8k72160
14.8k72160
add a comment |
add a comment |
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2
$begingroup$
Yes. (words to fill the comment)
$endgroup$
– Vinícius Novelli
May 3 '15 at 7:48
$begingroup$
As long as you agree that $infty = +infty$. I personally don't, and in calculus I usually teach that $infty$ means nothing. But Mathematica agrees with this shorthand.
$endgroup$
– Siminore
May 3 '15 at 7:50
$begingroup$
Well exactly infinity would not be defined, because it's a concept not a number. However, the notation that $lim_{xto infty}$ implies that $x$ is approaching infinity. If you directly say that it's an abbreviation, it won't be a good idea. It's the limit as $x$ approaches it.
$endgroup$
– Mann
May 3 '15 at 7:51
$begingroup$
@Siminore yes, $infty = +infty$ here. I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:55
$begingroup$
@Mann I think infinity could be used as a number to measure quantities that finite number , like real number, could not measure, infinity is greater than any assignable quantity or countable number, while “x tends to infinity”(x→∞) is actually an unending procedure.
$endgroup$
– iMath
May 3 '15 at 7:58