求阴影部分的面积（单位:cm） 求下列图中阴影部分的面积。(单位:厘米)
\u6c42\u4e0b\u9762\u56fe\u5f62\u4e2d\u9634\u5f71\u90e8\u5206\u7684\u9762\u79ef\uff0e\uff08\u5355\u4f4d\uff1acm\uff081\uff095\u00d75-3.14\u00d7\uff085\u00f72\uff092\u00f72=25-9.8125=15.1875\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0e\u7b54\uff1a\u9634\u5f71\u90e8\u5206\u9762\u79ef\u662f15.1875\u5e73\u65b9\u5398\u7c73\uff0e\uff082\uff093.14\u00d7\uff0852-32\uff09=3.14\u00d716=50.24\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0e\u7b54\u9634\u5f71\u90e8\u5206\u9762\u79ef\u662f50.24\u5e73\u65b9\u5398\u7c73\uff0e\uff083\uff0910\u00d76-3.14\u00d7\uff086\u00f72\uff092=60-28.26=31.74\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0e\u7b54\uff1a\u9634\u5f71\u90e8\u5206\u9762\u79ef\u662f31.74\u5e73\u65b9\u5398\u7c73\uff0e\uff084\uff093.14\u00d7\uff0816\u00f72\uff092\u00f72+16\u00d7\uff0816\u00f72\uff09\u00f72=100.48+64=164.48\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0e\u7b54\uff1a\u9634\u5f71\u90e8\u5206\u7684\u9762\u79ef\u662f164.48\u5e73\u65b9\u5398\u7c73\uff0e\uff085\uff09\uff0810+8\uff09\u00d7\uff088\u00f72\uff09\u00f72-3.14\u00d7\uff088\u00f72\uff092\u00f72=36-25.12=10.88\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0e\u7b54\uff1a\u9634\u5f71\u90e8\u5206\u7684\u9762\u79ef\u662f10.88\u5e73\u65b9\u5398\u7c73\uff0e\uff086\uff098\u00d78-3.14\u00d7\uff088\u00f72\uff092=64-50.24=13.76\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0e\u7b54\uff1a\u9634\u5f71\u90e8\u5206\u9762\u79ef\u662f13.76\u5e73\u65b9\u5398\u7c73\uff0e
3.14\u00d7(12/2)²-12²/2=41.04
\u9634\u5f71\u9762\u79ef=41.04\u00f72=20.52\u5e73\u65b9\u5398\u7c73
A半圆=B半圆
所以阴影部份刚好等于1/2个大圆的面积
阴影部份面积=1/2*3.14*2*2
=6.28
用割补法，得知
阴影部分等于大圆的面积的一半
阴影部分面积=1/2*3.14*2*2
=6.28
这是太极八卦的图形，是中心对称的，阴影和空白面积一样大。为整个圆面积的一半
求出圆的面积，再除以二就可以了
绛旓細绛旓細缁闃村奖闈㈢Н娣诲姞涓鏉＄孩鑹茶緟鍔╃嚎锛屽垎鎴愪袱涓挐瑙掍笁瑙掑舰 闈㈢НS=6脳6梅2+(8-6)脳8梅2 =18+8 =26
绛旓細澶х殑鍗婂渾闈㈢Н锛歋1=蟺R²/2=蟺脳4²/2=8蟺锛涘皬鐨勫崐鍦嗛潰绉細S2=蟺r²/2=蟺脳2²/2=2蟺銆傛墍浠ワ細S闃村奖=S1-S2=8蟺-2蟺=6蟺=6脳3.14=18.84锛坈m²锛夈傦紙2锛夊崐鍦嗙殑鐩村緞涓10cm锛屽垯鍗婂緞涓篟=5锛坈m锛锛屽洜姝ゆ褰㈢殑楂樺害涔熶负5cm銆傚崐鍦鐨勯潰绉細S1=蟺R²/2=...
绛旓細tg胃=4 / (4+8)=L / 8 鍒橪= 8/3 cm 闃村奖閮ㄥ垎鐨勯潰绉S=S1+S2 =( 4 - 8/3)脳8梅2+( 4 - 8/3)脳4梅2 =( 4 - 8/3)脳锛4+8锛壝2 =8cm²甯屾湜鑳藉府涓婁綘銆
绛旓細鍥炵瓟锛8 X 3=24
绛旓細闃村奖閮ㄥ垎闈㈢Н鍙互鐪嬫垚 骞宠鍥涜竟褰鐨勯潰绉鍑忓幓 涓涓瓑鑵扮洿瑙掍笁瑙掑舰鐨 闈㈢Н銆傚钩琛屽洓杈瑰舰闈㈢Н=搴暶楅珮 =20脳30=600骞虫柟鍘樼背 绛夎叞鐩磋涓夎褰㈤潰绉= 20脳20梅2=200骞虫柟鍘樼背 闃村奖闈㈢Н=600-200=400骞虫柟鍘樼背
绛旓細鍒嗘瀽锛氶槾褰遍儴鍒嗙殑闈㈢Н=澶ф鏂瑰舰闈㈢Н鐨勪竴鍗+灏忔鏂瑰舰闈㈢Н-鍙充笅澶т笁瑙掑舰闈㈢Н 瑙ｏ細澶ф鏂瑰舰闈㈢Н鐨勪竴鍗婃槸锛10脳10梅2=50骞虫柟鍘樼背 灏忔鏂瑰舰闈㈢Н鏄細8脳8=64骞虫柟鍘樼背 鍙充笅澶т笁瑙掑舰闈㈢Н鏄細锛10+8锛壝8梅2=72骞虫柟鍘樼背 闃村奖閮ㄥ垎闈㈢Н锛50+64-72=42骞虫柟鍘樼背銆
绛旓細澶ф鏂瑰舰鐨勯潰绉鏄15锛岄偅杈归暱灏辨槸鏍瑰彿15锛岄偅涔堝搴旂殑鍦嗙殑鐩村緞涔熸槸鏍瑰彿15锛岄潰绉氨鏄4鍒嗕箣15蟺锛岀劧鍚庡皬姝ｆ柟褰㈢殑杈归暱鏄2鍒嗕箣鏍瑰彿30锛岄潰绉氨鏄2鍒嗕箣15锛屾墍浠闃村奖閮ㄥ垎闈㈢Н灏辨槸鍦嗙殑闈㈢Н鍑忓幓灏忔鏂瑰舰鐨勯潰绉瓑浜4鍒嗕箣锛15蟺-30锛夈
绛旓細涓や釜鎵囧舰闈㈢Н鍜屽噺鍘绘鏂瑰舰闈㈢Н 3.14脳20脳20梅4脳2-20脳20=228骞虫柟鍘樼背
绛旓細s=(12+8)*3/2+3.14*4*4/2-3.14*3*3 =30-3.14 =26.86
绛旓細锛1锛夐槾褰遍儴鍒嗛潰绉=锛8+15锛壝楋紙8梅2锛壝2-锛8梅2锛²脳3.14梅2 =46-25.12 =20.88锛堝钩鏂瑰帢绫筹級锛2锛夐槾褰遍儴鍒嗛潰绉=10脳锛10脳2锛-锛10脳2锛壝10梅2 =200-100 =100锛堝钩鏂瑰帢绫筹級锛3锛夐槾褰遍儴鍒嗛潰绉=8²脳3.14梅4-锛8梅2锛²脳3.14梅2 =50.24-25.12 =25.12...
