원둘레: 두 판 사이의 차이

내용 삭제됨 내용 추가됨
원주각에서 가져옴
편집 요약 없음
5번째 줄:
== 공식 ==
: <math>c=\pi\cdot{d}.\,\!</math>
 
== 타원의 둘레 ==
=== 뮤어 1883 ===
[[토머스 뮤어]] 공식:
::<math>\begin{align}Pr
&\approx\left(\frac{a^{1.5}+b^{1.5}}{2}\right)^\frac{1}{1.5}=a\left(\frac{2+\cos^{3}\!\left(\alpha\right)}{2}\right)^\frac{2}{3},\\
&\quad\approx{a}\times\cos^2\!\left(\frac{\alpha}{2}\right)\left(1+\frac{1}{4}\tan^4\!\left(\frac{\alpha}{2}\right)\right).\end{align}\,\!</math>
=== 라마누잔-1914 (#1,#2) ===
[[스리니바사 라마누잔]]의 공식:
::<math>\begin{align}1.\;Pr&\approx\frac{1}{2}\Big(3(a+b)-\sqrt{\big(3a+b\big)\big(a+3b\big)}\Big),\\
&\quad=\frac{a}{2}\bigg(6\cos^2\!\left(\frac{\alpha}{2}\right)-\sqrt{\big(3+\cos\!\left(\alpha\right)\big)\big(1+3\cos\!\left(\alpha\right)\big)}\bigg);\end{align}\,\!</math>
 
::<math>\begin{align}2.\;Pr&\approx\frac{1}{2}\Big(a+b\Big)\Bigg(1+\frac{3\big(\frac{a-b}{a+b}\big)^2}{10+\sqrt{4-3\big(\frac{a-b}{a+b}\big)^2}}\Bigg);\\
&\quad=a\times\cos^2\!\left(\frac{\alpha}{2}\right)\Bigg(1+\frac{3\tan^4\!\big(\frac{\alpha}{2}\big)}{10+\sqrt{4-3\tan^4\!\big(\frac{\alpha}{2}\big)}}\Bigg).\end{align}\,\!</math>
 
a = 10000, b = a cos&#123;oε&#125;:
 
{|class="wikitable" HII
|-
! b !! Pr !! 라마누잔-#2 !! 라마누잔-#1 !! 뮤어
|-
|9975
||&nbsp;'''9987.50391&nbsp;11393'''&nbsp;
||&nbsp;'''9987.50391&nbsp;11393'''&nbsp;
||&nbsp;'''9987.50391&nbsp;11393'''&nbsp;
||&nbsp;'''9987.50391&nbsp;113'''89
|-
|9966
||&nbsp;'''9983.00723 73047'''
||&nbsp;'''9983.00723 73047'''
||&nbsp;'''9983.00723 73047'''
||&nbsp;'''9983.00723 730'''34
|-
|9950
||&nbsp;'''9975.01566 41666'''
||&nbsp;'''9975.01566 41666'''
||&nbsp;'''9975.01566 41666'''
||&nbsp;'''9975.01566 416'''04
|-
|9900
||&nbsp;'''9950.06281 41695'''
||&nbsp;'''9950.06281 41695'''
||&nbsp;'''9950.06281 41695'''
||&nbsp;'''9950.06281 4'''0704
|-
|9000
||&nbsp;'''9506.58008 71725'''
||&nbsp;'''9506.58008 71725'''
||&nbsp;'''9506.58008''' 67774
||&nbsp;'''9506.5'''7894 84209
|-
|8000
||&nbsp;'''9027.79927 77219'''
||&nbsp;'''9027.79927 77219'''
||&nbsp;'''9027.7992'''4 43886
||&nbsp;'''9027.7'''7786 62561
|-
|7500
||&nbsp;'''8794.70009 24247'''
||&nbsp;'''8794.70009 2424'''0
||&nbsp;'''8794'''.69994 52888
||&nbsp;'''8794'''.64324 65132
|-
|6667
||&nbsp;'''8417.02535 37669'''
||&nbsp;'''8417.02535 37'''460
||&nbsp;'''8417.02'''428 62059
||&nbsp;'''841'''6.81780 56370
|-
|5000
||&nbsp;'''7709.82212 59502'''
||&nbsp;'''7709.82212''' 24348
||&nbsp;'''7709.8'''0054 22510
||&nbsp;'''770'''8.38853 77837
|-
|3333
||&nbsp;'''7090.18347 61693'''
||&nbsp;'''7090.183'''24 21686
||&nbsp;'''70'''89.94281 35586
||&nbsp;'''70'''83.80287 96714
|-
|2500
||&nbsp;'''6826.49114 72168'''
||&nbsp;'''6826.4'''8944 11189
||&nbsp;'''682'''5.75998 22882
||&nbsp;'''68'''14.20222 31205
|-
|1000
||&nbsp;'''6468.01579 36089'''
||&nbsp;'''646'''7.94103 84016
||&nbsp;'''646'''2.57005 00576
||&nbsp;'''64'''31.72229 28418
|-
|&nbsp;100
||&nbsp;'''6367.94576 97209'''
||&nbsp;'''636'''6.42397 74408
||&nbsp;'''63'''46.16560 81001
||&nbsp;'''63'''03.80428 66621
|-
|&nbsp;&nbsp;10
||&nbsp;'''6366.22253 29150'''
||&nbsp;'''636'''3.81341 42880
||&nbsp;'''63'''40.31989 06242
||&nbsp;'''6'''299.73805 61141
|-
|&nbsp;&nbsp;&nbsp;1
||&nbsp;'''6366.19804 50617'''
||&nbsp;'''636'''3.65301 06191
||&nbsp;'''63'''39.80266 34498
||&nbsp;'''6'''299.60944 92105
|-
|[[:en:iota|iota]]
||&nbsp;'''6366.19772 36758'''
||&nbsp;'''636'''3.63636 36364
||&nbsp;'''63'''39.74596 21556
||&nbsp;'''6'''299.60524 94744
|}
 
== 원주각 ==