What's the domain of $f(x) = sqrt{x^2 - 4x + 5}$? [closed]
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What's the domain of $f(x) = sqrt{x^2 - 4x + 5}$ ?
Thanks
algebra-precalculus
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closed as off-topic by José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd Jan 29 at 16:12
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd
If this question can be reworded to fit the rules in the help center, please edit the question.
add a comment |
$begingroup$
What's the domain of $f(x) = sqrt{x^2 - 4x + 5}$ ?
Thanks
algebra-precalculus
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closed as off-topic by José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd Jan 29 at 16:12
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd
If this question can be reworded to fit the rules in the help center, please edit the question.
2
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I would say all real numbers
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– Dr. Sonnhard Graubner
Jan 29 at 7:11
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@Dr.SonnhardGraubner, I think you are right
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– BadAtGeometry
Jan 29 at 7:13
1
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... and how to show this? Hint $x^2 -4x +5 = x^2 -2times 2x + 2^2 +1 = (x-2)^2 +1$
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– Matti P.
Jan 29 at 7:15
add a comment |
$begingroup$
What's the domain of $f(x) = sqrt{x^2 - 4x + 5}$ ?
Thanks
algebra-precalculus
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What's the domain of $f(x) = sqrt{x^2 - 4x + 5}$ ?
Thanks
algebra-precalculus
algebra-precalculus
edited Jan 29 at 7:11


Chinnapparaj R
5,8602928
5,8602928
asked Jan 29 at 7:10
Sully Sully
21
21
closed as off-topic by José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd Jan 29 at 16:12
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd
If this question can be reworded to fit the rules in the help center, please edit the question.
closed as off-topic by José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd Jan 29 at 16:12
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Hans Lundmark, Claude Leibovici, Adrian Keister, Abcd
If this question can be reworded to fit the rules in the help center, please edit the question.
2
$begingroup$
I would say all real numbers
$endgroup$
– Dr. Sonnhard Graubner
Jan 29 at 7:11
$begingroup$
@Dr.SonnhardGraubner, I think you are right
$endgroup$
– BadAtGeometry
Jan 29 at 7:13
1
$begingroup$
... and how to show this? Hint $x^2 -4x +5 = x^2 -2times 2x + 2^2 +1 = (x-2)^2 +1$
$endgroup$
– Matti P.
Jan 29 at 7:15
add a comment |
2
$begingroup$
I would say all real numbers
$endgroup$
– Dr. Sonnhard Graubner
Jan 29 at 7:11
$begingroup$
@Dr.SonnhardGraubner, I think you are right
$endgroup$
– BadAtGeometry
Jan 29 at 7:13
1
$begingroup$
... and how to show this? Hint $x^2 -4x +5 = x^2 -2times 2x + 2^2 +1 = (x-2)^2 +1$
$endgroup$
– Matti P.
Jan 29 at 7:15
2
2
$begingroup$
I would say all real numbers
$endgroup$
– Dr. Sonnhard Graubner
Jan 29 at 7:11
$begingroup$
I would say all real numbers
$endgroup$
– Dr. Sonnhard Graubner
Jan 29 at 7:11
$begingroup$
@Dr.SonnhardGraubner, I think you are right
$endgroup$
– BadAtGeometry
Jan 29 at 7:13
$begingroup$
@Dr.SonnhardGraubner, I think you are right
$endgroup$
– BadAtGeometry
Jan 29 at 7:13
1
1
$begingroup$
... and how to show this? Hint $x^2 -4x +5 = x^2 -2times 2x + 2^2 +1 = (x-2)^2 +1$
$endgroup$
– Matti P.
Jan 29 at 7:15
$begingroup$
... and how to show this? Hint $x^2 -4x +5 = x^2 -2times 2x + 2^2 +1 = (x-2)^2 +1$
$endgroup$
– Matti P.
Jan 29 at 7:15
add a comment |
2 Answers
2
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oldest
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Assuming that you are considering this as a function from real numbers to real numbers, you can rearrange to write:$$f(x)=sqrt{(x-2)^2+1}$$
So the radicand is positive no matter what real number $x$ is, and therefore the domain is all real numbers.
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add a comment |
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The domain is all real numbers. See this graph.
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a graph is not a proof
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– J. W. Tanner
Jan 29 at 14:58
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To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
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– TheSimpliFire
Feb 13 at 9:35
add a comment |
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Assuming that you are considering this as a function from real numbers to real numbers, you can rearrange to write:$$f(x)=sqrt{(x-2)^2+1}$$
So the radicand is positive no matter what real number $x$ is, and therefore the domain is all real numbers.
$endgroup$
add a comment |
$begingroup$
Assuming that you are considering this as a function from real numbers to real numbers, you can rearrange to write:$$f(x)=sqrt{(x-2)^2+1}$$
So the radicand is positive no matter what real number $x$ is, and therefore the domain is all real numbers.
$endgroup$
add a comment |
$begingroup$
Assuming that you are considering this as a function from real numbers to real numbers, you can rearrange to write:$$f(x)=sqrt{(x-2)^2+1}$$
So the radicand is positive no matter what real number $x$ is, and therefore the domain is all real numbers.
$endgroup$
Assuming that you are considering this as a function from real numbers to real numbers, you can rearrange to write:$$f(x)=sqrt{(x-2)^2+1}$$
So the radicand is positive no matter what real number $x$ is, and therefore the domain is all real numbers.
edited Jan 29 at 15:00
answered Jan 29 at 7:16


alex.jordanalex.jordan
39.6k660122
39.6k660122
add a comment |
add a comment |
$begingroup$
The domain is all real numbers. See this graph.
$endgroup$
$begingroup$
a graph is not a proof
$endgroup$
– J. W. Tanner
Jan 29 at 14:58
$begingroup$
To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
$endgroup$
– TheSimpliFire
Feb 13 at 9:35
add a comment |
$begingroup$
The domain is all real numbers. See this graph.
$endgroup$
$begingroup$
a graph is not a proof
$endgroup$
– J. W. Tanner
Jan 29 at 14:58
$begingroup$
To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
$endgroup$
– TheSimpliFire
Feb 13 at 9:35
add a comment |
$begingroup$
The domain is all real numbers. See this graph.
$endgroup$
The domain is all real numbers. See this graph.
answered Jan 29 at 7:12
BadAtGeometryBadAtGeometry
300215
300215
$begingroup$
a graph is not a proof
$endgroup$
– J. W. Tanner
Jan 29 at 14:58
$begingroup$
To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
$endgroup$
– TheSimpliFire
Feb 13 at 9:35
add a comment |
$begingroup$
a graph is not a proof
$endgroup$
– J. W. Tanner
Jan 29 at 14:58
$begingroup$
To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
$endgroup$
– TheSimpliFire
Feb 13 at 9:35
$begingroup$
a graph is not a proof
$endgroup$
– J. W. Tanner
Jan 29 at 14:58
$begingroup$
a graph is not a proof
$endgroup$
– J. W. Tanner
Jan 29 at 14:58
$begingroup$
To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
$endgroup$
– TheSimpliFire
Feb 13 at 9:35
$begingroup$
To second @J.W.Tanner, this is at best a comment. Plots are never rigorous proofs of anything. Please consider deleting this and transferring it to the comments section.
$endgroup$
– TheSimpliFire
Feb 13 at 9:35
add a comment |
2
$begingroup$
I would say all real numbers
$endgroup$
– Dr. Sonnhard Graubner
Jan 29 at 7:11
$begingroup$
@Dr.SonnhardGraubner, I think you are right
$endgroup$
– BadAtGeometry
Jan 29 at 7:13
1
$begingroup$
... and how to show this? Hint $x^2 -4x +5 = x^2 -2times 2x + 2^2 +1 = (x-2)^2 +1$
$endgroup$
– Matti P.
Jan 29 at 7:15