Algebra för Ma1A: Skillnad mellan sidversioner
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Wu's Squaring Trick, named after the famous Scott Wu, is a technique used to quickly square numbers over 25 in your head. It uses the identity | Wu's Squaring Trick, named after the famous Scott Wu, is a technique used to quickly square numbers over 25 in your head. It uses the identity | ||
: | : <math> n^2 = (n-25) \cdot 100 + (n-50)^2 </math> | ||
For example, | For example, | ||
Rad 11: | Rad 11: | ||
: <math> 62^2 = 37 \cdot 100 + 12^2 = 3844 </math> | : <math> 62^2 = 37 \cdot 100 + 12^2 = 3844 </math> | ||
: | : | ||
: | : <math> 44^2 = 19 \cdot 100 + 6^2 = 1936 </math> | ||
: | : | ||
: | : <math> 77^2 = 52 \cdot 100 + 27^2 = 5929 </math> | ||
These mental computations can be done very quickly with just a little practice, so amaze your friends with how fast you can square two digit numbers! | These mental computations can be done very quickly with just a little practice, so amaze your friends with how fast you can square two digit numbers! |
Versionen från 1 oktober 2014 kl. 21.21
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Wu's Squaring Trick, named after the famous Scott Wu, is a technique used to quickly square numbers over 25 in your head. It uses the identity
- [math]\displaystyle{ n^2 = (n-25) \cdot 100 + (n-50)^2 }[/math]
For example,
- [math]\displaystyle{ 62^2 = 37 \cdot 100 + 12^2 = 3844 }[/math]
- [math]\displaystyle{ 44^2 = 19 \cdot 100 + 6^2 = 1936 }[/math]
- [math]\displaystyle{ 77^2 = 52 \cdot 100 + 27^2 = 5929 }[/math]
These mental computations can be done very quickly with just a little practice, so amaze your friends with how fast you can square two digit numbers!