Definition of Enlargement (Homothetic Transformation: Negative Scale Factor)












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$textbf{Question:}$ It says on Wikipedia that an enlargement of a figure can be described when the scale factor exceeds one. Shouldn't it be when the absolute value of the scale factor exceeds one (i.e. $|lambda|>1$)?



$textbf{Opinion:}$ I also wanted to point out this question has been brought up here as well. The problem I see here is that the definition for $lambda$ is never defined to be new distance over old. It is clear that a figure is getting larger iff $|lambda|>1$ for this situation. I think an enlargement should be defined here to be when $|lambda|>1$ which then implies $|lambda|$ is the ratio of which distances are multiplied. However, that is just my opinion.










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  • 1




    $begingroup$
    If you read that Wikipedia entry more carefully, you'll se that the scale factor is indeed defined as $|lambda|$.
    $endgroup$
    – Aretino
    Dec 29 '18 at 12:31


















1












$begingroup$


$textbf{Question:}$ It says on Wikipedia that an enlargement of a figure can be described when the scale factor exceeds one. Shouldn't it be when the absolute value of the scale factor exceeds one (i.e. $|lambda|>1$)?



$textbf{Opinion:}$ I also wanted to point out this question has been brought up here as well. The problem I see here is that the definition for $lambda$ is never defined to be new distance over old. It is clear that a figure is getting larger iff $|lambda|>1$ for this situation. I think an enlargement should be defined here to be when $|lambda|>1$ which then implies $|lambda|$ is the ratio of which distances are multiplied. However, that is just my opinion.










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    If you read that Wikipedia entry more carefully, you'll se that the scale factor is indeed defined as $|lambda|$.
    $endgroup$
    – Aretino
    Dec 29 '18 at 12:31
















1












1








1





$begingroup$


$textbf{Question:}$ It says on Wikipedia that an enlargement of a figure can be described when the scale factor exceeds one. Shouldn't it be when the absolute value of the scale factor exceeds one (i.e. $|lambda|>1$)?



$textbf{Opinion:}$ I also wanted to point out this question has been brought up here as well. The problem I see here is that the definition for $lambda$ is never defined to be new distance over old. It is clear that a figure is getting larger iff $|lambda|>1$ for this situation. I think an enlargement should be defined here to be when $|lambda|>1$ which then implies $|lambda|$ is the ratio of which distances are multiplied. However, that is just my opinion.










share|cite|improve this question











$endgroup$




$textbf{Question:}$ It says on Wikipedia that an enlargement of a figure can be described when the scale factor exceeds one. Shouldn't it be when the absolute value of the scale factor exceeds one (i.e. $|lambda|>1$)?



$textbf{Opinion:}$ I also wanted to point out this question has been brought up here as well. The problem I see here is that the definition for $lambda$ is never defined to be new distance over old. It is clear that a figure is getting larger iff $|lambda|>1$ for this situation. I think an enlargement should be defined here to be when $|lambda|>1$ which then implies $|lambda|$ is the ratio of which distances are multiplied. However, that is just my opinion.







geometry analytic-geometry






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share|cite|improve this question













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share|cite|improve this question








edited Dec 28 '18 at 22:41







W. G.

















asked Dec 28 '18 at 20:41









W. G.W. G.

6621717




6621717








  • 1




    $begingroup$
    If you read that Wikipedia entry more carefully, you'll se that the scale factor is indeed defined as $|lambda|$.
    $endgroup$
    – Aretino
    Dec 29 '18 at 12:31
















  • 1




    $begingroup$
    If you read that Wikipedia entry more carefully, you'll se that the scale factor is indeed defined as $|lambda|$.
    $endgroup$
    – Aretino
    Dec 29 '18 at 12:31










1




1




$begingroup$
If you read that Wikipedia entry more carefully, you'll se that the scale factor is indeed defined as $|lambda|$.
$endgroup$
– Aretino
Dec 29 '18 at 12:31






$begingroup$
If you read that Wikipedia entry more carefully, you'll se that the scale factor is indeed defined as $|lambda|$.
$endgroup$
– Aretino
Dec 29 '18 at 12:31












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