The magic of Fibonacci numbers | Arthur Benjamin | TED

5,721,933 views ・ 2013-11-08

TED


Za predvajanje videoposnetka dvakrat kliknite na spodnje angleške podnapise.

Translator: Petra Zajc Reviewer: Nika Kotnik
00:12
So why do we learn mathematics?
0
12613
3039
Torej, zakaj se učimo matematike?
00:15
Essentially, for three reasons:
1
15652
2548
V glavnem imamo tri razloge:
00:18
calculation,
2
18200
1628
računanje
00:19
application,
3
19828
1900
uporaba
00:21
and last, and unfortunately least
4
21728
2687
in na koncu še razlog, ki je žal daleč zadaj,
00:24
in terms of the time we give it,
5
24415
2105
kar se tiče časa, ki mu ga namenimo,
00:26
inspiration.
6
26520
1922
navdih.
00:28
Mathematics is the science of patterns,
7
28442
2272
Matematika je znanost vzorcev
00:30
and we study it to learn how to think logically,
8
30714
3358
in učimo se je, da se naučimo razmišljati logično,
00:34
critically and creatively,
9
34072
2527
kritično in ustvarjalno.
00:36
but too much of the mathematics that we learn in school
10
36599
2926
Ampak prevečkrat za matematiko, ki jo učijo v šoli,
00:39
is not effectively motivated,
11
39525
2319
ni učinkovite motivacije
00:41
and when our students ask,
12
41844
1425
in ko nas učenci vprašajo:
00:43
"Why are we learning this?"
13
43269
1675
"Zakaj se to učimo?"
00:44
then they often hear that they'll need it
14
44944
1961
pogosto slišijo, da bodo znanje potrebovali
00:46
in an upcoming math class or on a future test.
15
46905
3265
pri pouku matematike ali pri naslednjem testu.
00:50
But wouldn't it be great
16
50170
1802
Ampak, ali ne bi bilo krasno,
00:51
if every once in a while we did mathematics
17
51972
2518
če bi kdaj pa kdaj uporabljali matematiko
00:54
simply because it was fun or beautiful
18
54490
2949
preprosto zato, ker je zabavna ali lepa
00:57
or because it excited the mind?
19
57439
2090
ali pa ker spodbuja razmišljanje?
00:59
Now, I know many people have not
20
59529
1722
Veliko ljudi ni imelo priložnosti,
01:01
had the opportunity to see how this can happen,
21
61251
2319
da bi videli, kako se to lahko zgodi,
01:03
so let me give you a quick example
22
63570
1829
zato vam bom na hitro pokazal primer
01:05
with my favorite collection of numbers,
23
65399
2341
s svojo najljubšo zbirko številk,
01:07
the Fibonacci numbers. (Applause)
24
67740
2728
Fibonaccijevimi števili. (Aplavz)
01:10
Yeah! I already have Fibonacci fans here.
25
70468
2052
To! Tu je nekaj Fibonaccijevih oboževalcev.
01:12
That's great.
26
72520
1316
Odlično.
01:13
Now these numbers can be appreciated
27
73836
2116
Torej, ta števila so krasna
01:15
in many different ways.
28
75952
1878
na veliko različnih načinov.
01:17
From the standpoint of calculation,
29
77830
2709
Z vidika računanja
01:20
they're as easy to understand
30
80539
1677
so tako lahko razumljiva
01:22
as one plus one, which is two.
31
82216
2554
kot ena plus ena, kar je dva.
01:24
Then one plus two is three,
32
84770
2003
Potem imamo ena plus dva je tri,
01:26
two plus three is five, three plus five is eight,
33
86773
3014
dva plus tri je pet, tri plus pet je osem
01:29
and so on.
34
89787
1525
in tako naprej.
01:31
Indeed, the person we call Fibonacci
35
91312
2177
V resnici se je oseba, ki ji pravimo Fibonacci,
01:33
was actually named Leonardo of Pisa,
36
93489
3180
imenovala Leonardo Pisano
01:36
and these numbers appear in his book "Liber Abaci,"
37
96669
3053
in ta števila so zapisana v njegovi knjigi "Liber Abaci",
01:39
which taught the Western world
38
99722
1650
ki je zahodni svet naučila
01:41
the methods of arithmetic that we use today.
39
101372
2827
aritmetičnih metod, ki jih uporabljamo danes.
01:44
In terms of applications,
40
104199
1721
Kar se tiče uporabe,
01:45
Fibonacci numbers appear in nature
41
105920
2183
se Fibonaccijeva števila v naravi pojavljajo
01:48
surprisingly often.
42
108103
1857
presenetljivo pogosto.
01:49
The number of petals on a flower
43
109960
1740
Število cvetnih listov na roži
01:51
is typically a Fibonacci number,
44
111700
1862
je ponavadi Fibonaccijevo število,
01:53
or the number of spirals on a sunflower
45
113562
2770
pa tudi število spiral na sončnici
01:56
or a pineapple
46
116332
1411
ali ananasu
01:57
tends to be a Fibonacci number as well.
47
117743
2394
je pogosto Fibonaccijevo število.
02:00
In fact, there are many more applications of Fibonacci numbers,
48
120137
3503
Pravzaprav je možnosti uporabe Fibonaccijevih števil veliko več,
02:03
but what I find most inspirational about them
49
123640
2560
a sam mislim, da so pri njih najbolj navdušujoči
02:06
are the beautiful number patterns they display.
50
126200
2734
lepi številski vzorci, ki jih ustvarjajo.
02:08
Let me show you one of my favorites.
51
128934
2194
Pokazal vam bom enega od svojih najljubših.
02:11
Suppose you like to square numbers,
52
131128
2221
Recimo, da radi kvadrirate števila,
02:13
and frankly, who doesn't? (Laughter)
53
133349
2675
konec koncev, kdo jih pa ne? (Smeh)
02:16
Let's look at the squares
54
136040
2240
Poglejmo kvadrate
02:18
of the first few Fibonacci numbers.
55
138280
1851
prvih nekaj Fibonaccijevih števil.
02:20
So one squared is one,
56
140131
2030
Torej, ena na kvadrat je ena,
02:22
two squared is four, three squared is nine,
57
142161
2317
dva na kvadrat je štiri, tri na kvadrat je devet,
02:24
five squared is 25, and so on.
58
144478
3173
pet na kvadrat je 25 in tako naprej.
02:27
Now, it's no surprise
59
147651
1901
No, ni prav presenetljivo,
02:29
that when you add consecutive Fibonacci numbers,
60
149552
2828
da, ko seštejemo zaporedna Fibonaccijeva števila,
02:32
you get the next Fibonacci number. Right?
61
152380
2032
dobimo naslednje Fibonaccijevo število. Drži?
02:34
That's how they're created.
62
154412
1395
Tako nastanejo.
02:35
But you wouldn't expect anything special
63
155807
1773
Ne bi pa pričakovali, da se zgodi
02:37
to happen when you add the squares together.
64
157580
3076
kaj posebnega, ko seštejemo njihove kvadrate.
02:40
But check this out.
65
160656
1346
Pa poglejte zdaj tole.
02:42
One plus one gives us two,
66
162002
2001
Ena plus ena je dva
02:44
and one plus four gives us five.
67
164003
2762
in ena plus štiri je pet.
02:46
And four plus nine is 13,
68
166765
2195
In štiri plus devet je 13,
02:48
nine plus 25 is 34,
69
168960
3213
devet plus 25 je 34,
02:52
and yes, the pattern continues.
70
172173
2659
in ja, vzorec se nadaljuje.
02:54
In fact, here's another one.
71
174832
1621
V bistvu imamo še en vzorec.
02:56
Suppose you wanted to look at
72
176453
1844
Recimo, da bi hoteli pogledati
02:58
adding the squares of the first few Fibonacci numbers.
73
178297
2498
seštevek kvadratov prvih nekaj Fibonaccijevih števil.
03:00
Let's see what we get there.
74
180795
1608
Pa poglejmo, kaj dobimo.
03:02
So one plus one plus four is six.
75
182403
2139
Torej, ena plus ena plus štiri je šest.
03:04
Add nine to that, we get 15.
76
184542
3005
Dodajmo še devet in dobimo 15.
03:07
Add 25, we get 40.
77
187547
2213
Dodamo 25 in dobimo 40.
03:09
Add 64, we get 104.
78
189760
2791
Dodamo 64, dobimo 104.
03:12
Now look at those numbers.
79
192551
1652
Zdaj pa poglejmo ta števila.
03:14
Those are not Fibonacci numbers,
80
194203
2384
To niso Fibonaccijeva števila,
03:16
but if you look at them closely,
81
196587
1879
ampak, če jih pogledate od blizu,
03:18
you'll see the Fibonacci numbers
82
198466
1883
boste videli, da se Fibonaccijeva števila
03:20
buried inside of them.
83
200349
2178
skrivajo v njih.
03:22
Do you see it? I'll show it to you.
84
202527
2070
Jih vidite? Vam bom pokazal.
03:24
Six is two times three, 15 is three times five,
85
204597
3733
Šest je dva krat tri, 15 je tri krat pet,
03:28
40 is five times eight,
86
208330
2059
40 je pet krat osem,
03:30
two, three, five, eight, who do we appreciate?
87
210389
2928
dva, tri, pet, osem, koga občudujemo?
03:33
(Laughter)
88
213317
1187
(Smeh)
03:34
Fibonacci! Of course.
89
214504
2155
Fibonaccija! Jasno.
03:36
Now, as much fun as it is to discover these patterns,
90
216659
3783
Zelo zabavno je odkrivati vzorce,
03:40
it's even more satisfying to understand
91
220442
2482
a v še večje zadovoljstvo je razumeti
03:42
why they are true.
92
222924
1958
zakaj držijo.
03:44
Let's look at that last equation.
93
224882
1889
Poglejmo zadnjo enačbo.
03:46
Why should the squares of one, one, two, three, five and eight
94
226771
3868
Zakaj mora seštevek kvadratov od ena, ena, dva, tri, pet in osem
03:50
add up to eight times 13?
95
230639
2545
znašati osem krat 13?
03:53
I'll show you by drawing a simple picture.
96
233184
2961
To vam bom pokazal s preprosto sliko.
03:56
We'll start with a one-by-one square
97
236145
2687
Začeli bomo s kvadratom ena krat ena
03:58
and next to that put another one-by-one square.
98
238832
4165
in zraven njega narisali še en kvadrat ena krat ena.
04:02
Together, they form a one-by-two rectangle.
99
242997
3408
Skupaj sestavljata pravokotnik ena krat dva.
04:06
Beneath that, I'll put a two-by-two square,
100
246405
2549
Pod njega bom narisal kvadrat dva krat dva,
04:08
and next to that, a three-by-three square,
101
248954
2795
zraven njega pa kvadrat tri krat tri,
04:11
beneath that, a five-by-five square,
102
251749
2001
pod njega kvadrat pet krat pet
04:13
and then an eight-by-eight square,
103
253750
1912
in nato kvadrat osem krat osem,
04:15
creating one giant rectangle, right?
104
255662
2572
in tako sem sestavil ogromen pravokotnik.
04:18
Now let me ask you a simple question:
105
258234
1916
Zdaj vam bom postavil preprosto vprašanje:
04:20
what is the area of the rectangle?
106
260150
3656
Kolikšna je ploščina pravokotnika?
04:23
Well, on the one hand,
107
263806
1971
No, po svoje
04:25
it's the sum of the areas
108
265777
2530
je vsota ploščin
04:28
of the squares inside it, right?
109
268307
1866
vseh kvadratov v njem, drži?
04:30
Just as we created it.
110
270173
1359
Kot smo ga naredili.
04:31
It's one squared plus one squared
111
271532
2172
Ena na kvadrat plus ena na kvadrat
04:33
plus two squared plus three squared
112
273704
2233
plus dva na kvadrat plus tri na kvadrat
04:35
plus five squared plus eight squared. Right?
113
275937
2599
plus pet na kvadrat plus osem na kvadrat.
04:38
That's the area.
114
278536
1857
To je ploščina.
04:40
On the other hand, because it's a rectangle,
115
280393
2326
Po drugi strani pa, ker je pravokotnik,
04:42
the area is equal to its height times its base,
116
282719
3648
je ploščina enaka višini krat širini
04:46
and the height is clearly eight,
117
286367
2047
in višina je očitno osem,
04:48
and the base is five plus eight,
118
288414
2903
širina pa pet plus osem,
04:51
which is the next Fibonacci number, 13. Right?
119
291317
3938
kar je naslednje Fibonaccijevo število, 13. Je tako?
04:55
So the area is also eight times 13.
120
295255
3363
Tako imamo ploščino osem krat 13.
04:58
Since we've correctly calculated the area
121
298618
2262
Ker smo pravilno izračunali ploščino
05:00
two different ways,
122
300880
1687
na dva različna načina,
05:02
they have to be the same number,
123
302567
2172
moramo dobiti enako številko
05:04
and that's why the squares of one, one, two, three, five and eight
124
304739
3391
in zato je seštevek kvadratov od ena, ena, dva, tri, pet in osem
05:08
add up to eight times 13.
125
308130
2291
skupaj osem krat 13.
05:10
Now, if we continue this process,
126
310421
2374
Če nadaljujemo s tem postopkom,
05:12
we'll generate rectangles of the form 13 by 21,
127
312795
3978
bomo ustvarili pravokotnike s stranicami 13 krat 21,
05:16
21 by 34, and so on.
128
316773
2394
21 krat 34 in tako naprej.
05:19
Now check this out.
129
319167
1409
Zdaj pa poglejte tole.
05:20
If you divide 13 by eight,
130
320576
2193
Če 13 delimo z osem,
05:22
you get 1.625.
131
322769
2043
dobimo 1,625.
05:24
And if you divide the larger number by the smaller number,
132
324812
3427
In če delimo večje število z manjšim številom,
05:28
then these ratios get closer and closer
133
328239
2873
se razmerje vedno bolj približuje
05:31
to about 1.618,
134
331112
2653
okoli 1,618,
05:33
known to many people as the Golden Ratio,
135
333765
3301
kar veliko ljudi pozna kot zlati rez,
05:37
a number which has fascinated mathematicians,
136
337066
2596
število, ki je stoletja navduševalo
05:39
scientists and artists for centuries.
137
339662
3246
matematike, znanstvenike in umetnike.
05:42
Now, I show all this to you because,
138
342908
2231
To vam kažem, ker,
05:45
like so much of mathematics,
139
345139
2025
kot toliko matematike,
05:47
there's a beautiful side to it
140
347164
1967
v sebi skriva nekaj lepega,
05:49
that I fear does not get enough attention
141
349131
2015
čemur mislim, da v naših šolah žal
05:51
in our schools.
142
351146
1567
ne posvečamo dovolj pozornosti.
05:52
We spend lots of time learning about calculation,
143
352713
2833
Veliko časa se učimo o računanju,
05:55
but let's not forget about application,
144
355546
2756
ampak ne smemo pozabiti na uporabo,
05:58
including, perhaps, the most important application of all,
145
358302
3454
vključno z morda najpomembnejšo uporabo,
06:01
learning how to think.
146
361756
2076
da se naučimo, kako razmišljati.
06:03
If I could summarize this in one sentence,
147
363832
1957
Če bi lahko to zajel v enem stavku,
06:05
it would be this:
148
365789
1461
bi rekel tole:
06:07
Mathematics is not just solving for x,
149
367250
3360
Matematika ni samo iskanje x-a,
06:10
it's also figuring out why.
150
370610
2925
ampak tudi smisla.
06:13
Thank you very much.
151
373535
1815
Najlepša hvala.
06:15
(Applause)
152
375350
4407
(Aplavz)
O tej spletni strani

Na tem mestu boste našli videoposnetke na YouTubu, ki so uporabni za učenje angleščine. Ogledali si boste lekcije angleščine, ki jih poučujejo vrhunski učitelji z vsega sveta. Z dvoklikom na angleške podnapise, ki so prikazani na vsaki strani z videoposnetki, lahko predvajate videoposnetek od tam. Podnapisi se pomikajo sinhronizirano s predvajanjem videoposnetka. Če imate kakršne koli pripombe ali zahteve, nam pišite prek tega obrazca za stike.

https://forms.gle/WvT1wiN1qDtmnspy7