5,6,7,12任选三个可以组成多少个三角形 3、4、5、6、7,可各有无限个,可组成多少个不同规格的三角...
\u4e94\u6761\u957f\u5ea6\u5206\u522b\u662f2\u30013\u30014\u30015\u30016\u7684\u7ebf\u6bb5 \u4efb\u9009\u4e09\u6761\u53ef\u4ee5\u7ec4\u6210\u591a\u5c11\u4e2a\u4e09\u89d2\u5f62?\u5b83\u4eec\u7684\u8fb9\u957f\u5206\u522b\u662f\uff1f\u8fb9\u957f\u5206\u522b\u4e3a\uff082\uff0c3\uff0c4\uff09\uff082\uff0c4\uff0c5\uff09\uff082\uff0c5\uff0c6\uff09\uff083\uff0c4\uff0c5\uff09\uff083\uff0c4\uff0c6\uff09\uff083\uff0c5\uff0c6\uff09\uff084\uff0c5\uff0c6\uff09\u51717\u79cd\u3002
\u5171\u80fd\u7ec4\u621032\u4e2a\u4e0d\u540c\u89c4\u683c\u7684\u4e09\u89d2\u5f62\u3002
1\u3001\u7b49\u8fb9\u4e09\u89d2\u5f62\uff1a5\u4e2a\uff0c\u5b83\u4eec\u7684\u8fb9\u957f\u5206\u522b\u662f3\u30014\u30015\u30016\u30017\u3002
2\u3001\u7b49\u8170\u4e09\u89d2\u5f62\uff1a\u6bcf\u79cd\u76f8\u540c\u7684\u6570\u5b57\u80fd\u4e0e\u53e6\u5916\u56db\u4e2a\u6570\u5b57\u5206\u522b\u7ec4\u6210\u4e00\u7ec4\uff0c\u8fd9\u6837\u5c31\u80fd\u7ec4\u62104\u7ec4\uff0c\u67095\u79cd\u4e0d\u540c\u7684\u6570\u5b57\uff0c\u6240\u4ee5\u80fd\u7ec4\u62104\u00d75\uff1d20\uff08\u7ec4\uff09\u3002\u4f46\u662f\u5728\u8fd920\u7ec4\u6570\u4e2d\uff0c3\u30013\u30016\u548c3\u30013\u30017\u662f\u4e0d\u80fd\u7ec4\u6210\u4e09\u89d2\u5f62\u7684\uff3b\u5fc5\u987b\u8981\u6c42\u4efb\u610f\u4e24\u6570\u7684\u548c\u5927\u4e8e\u7b2c\u4e09\u6570\uff3d\uff0c\u2234\u7b49\u8170\u4e09\u89d2\u5f62\u7684\u79cd\u6570\uff1d20\uff0d2\uff1d18\uff08\u79cd\uff09\u3002
3\u3001\u4e0d\u7b49\u8fb9\u4e09\u89d2\u5f62\uff1a5\u4e2a\u6570\u90093\u4e2a\u7684\u7ec4\u5408\uff0c\u7ec4\u5408\u6570\uff1d5\u00d74\u00d73/\uff083\u00d72\u00d71\uff09\uff1d10\uff0c\u5728\u8fd910\u7ec4\u6570\u4e2d\uff0c3\u30014\u30017\u8fd9\u4e00\u7ec4\u662f\u4e0d\u80fd\u7ec4\u6210\u4e09\u89d2\u5f62\u7684\uff0c\u2234\u4e0d\u7b49\u8fb9\u4e09\u89d2\u5f62\u79cd\u6570\uff1d10\uff0d1\uff1d9\uff08\u79cd\uff09\u3002
\u2234\u6ee1\u8db3\u6761\u4ef6\u7684\u4e09\u89d2\u5f62\u79cd\u6570\uff1d5\uff0b18\uff0b9\uff1d32\uff08\u79cd\uff09\u3002
567,
5,6,12
两种情况:要求两边之和大于第三边啊。
不可重复么
5,6,7,;6,7,12两种
5,6,7 6,7,12 (两边之和大于第三边,两边之差小于第三边)
2个 5,7,12和6,7,12
绛旓細6+9=15 鈥︹7+8=15鈥︹
绛旓細鍋囪杩12涓暟瀛楁槸1銆2銆3銆4銆5銆6銆7銆8銆9銆10銆11銆12锛涓嶈冭檻椤哄簭銆傞鍏堜粠12涓暟瀛椾腑閫夊嚭3涓鏁板瓧涓娉ㄤ笁涓笁锛屽彲浠鐢ㄧ粍鍚堢殑鏂规硶璁$畻锛欳(12,3) = 220銆傚洜涓哄寮忎腑瑕侀3涓暟瀛楋紝鎵浠ヤ竴娉ㄥ寮忎笁涓涓夊彲浠鐢3涓暟瀛椾互涓婄殑缁勫悎鏋勬垚銆傚亣璁鹃変簡k涓暟瀛楄繘琛岀粍鍚堬紝閭d箞涓鍏辨湁C(12,k)涓彲鑳界殑缁...
绛旓細5銆345锛堝彲浠ョ粍鍚堝叚涓暟锛夛細345銆354銆453銆435銆534銆543 6銆357锛堝彲浠ョ粍鍚堝叚涓暟锛夛細357銆375銆537銆573銆735銆753 7銆456锛堝彲浠ョ粍鍚堝叚涓暟锛夛細456銆465銆546銆564銆645銆654 8銆567锛堝彲浠ョ粍鍚堝叚涓暟锛夛細567銆576銆657銆675銆756銆765 ...
绛旓細(7,6,z),z=5,鈥︹︼紝2锛氬叡4涓紱鈥︹︽绫诲叡6涓(6,5,z),z=4,3,2:鍏3涓锛涒︹︽绫诲叡4涓傦紙5,4,3锛夛紝锛5,4锛2锛夛紝锛4,3,2锛夛細3涓傛昏鍙粍鎴16+12+9+6+4+3=50涓笁瑙掑舰銆
绛旓細锛1銆2銆3銆4锛..鈶狅紱锛5銆6銆7銆8锛..鈶★紱锛9銆10銆11銆12锛..鈶.绗竴绉:鎶娾憼涓庘憽缁勬斁鍦ㄥぉ骞充袱绔О銆傜粨鏋滄湁涓ょ鎯呭喌锛氫竴绉嶆槸骞筹紱鍙︿竴绉嶆槸涓嶅钩锛屼笉濡ㄥ亣璁剧粍鈶犻噸浜庣粍鈶°傚厛鏉ョ湅骞崇殑鎯呭喌銆傚垯1-8鍙风悆鍏ㄩ儴姝e父銆傛鍝佸繀鍦ㄧ粍鈶紝鍗冲湪9-12鍙风悆涓傚湪9-12鍙风悆涓浠婚3涓紝涓嶅Θ閫夛紙9銆...
绛旓細鏄15涓 3+6+6=15涓紝瑕佸ソ濂藉涔犲摝锛屼笉浼氱殑闂垜鍚э紝鎴戜細涓涓涓轰綘瑙g瓟
绛旓細C3 /12*C3/ 9*C3 /6*C3/3 闄や互A4/4 C3/12琛ㄧず12涓娊3涓鐨勭粍鍚.=12*11*10*9*8*7*6*5*4/锛3*2*1*3*2*1*3*2*1锛/锛4*3*2*1锛=15400.涓轰粈涔堥櫎浠4/4,鏄洜涓轰綘鎬诲叡鏈4缁勬暟,杩欓噷鍏堝彇1,2,3,鍜屽厛鍙4,5,6鏄绠楅噸澶嶄簡....
绛旓細锛1銆2銆3銆4锛..鈶狅紱锛5銆6銆7銆8锛..鈶★紱锛9銆10銆11銆12锛..鈶.绗竴绉:鎶娾憼涓庘憽缁勬斁鍦ㄥぉ骞充袱绔О銆傜粨鏋滄湁涓ょ鎯呭喌锛氫竴绉嶆槸骞筹紱鍙︿竴绉嶆槸涓嶅钩锛屼笉濡ㄥ亣璁剧粍鈶犻噸浜庣粍鈶°傚厛鏉ョ湅骞崇殑鎯呭喌銆傚垯1-8鍙风悆鍏ㄩ儴姝e父銆傛鍝佸繀鍦ㄧ粍鈶紝鍗冲湪9-12鍙风悆涓傚湪9-12鍙风悆涓浠婚3涓紝涓嶅Θ閫夛紙9銆...
绛旓細5鍙4/7锛5鍙6/7锛5鍙3/4銆5鍙2/3銆傛湁6涓傛暣鏁伴儴鍒嗘槸6鐨勶細6鍙2/7锛6鍙3/7锛6鍙4/7锛6鍙5/7锛6鍙2/5锛6鍙3/5锛6鍙4/5锛6鍙3/4锛6鍙2/3銆傛湁9涓傛暣鏁伴儴鍒嗘槸7鐨勶細7鍙5/6锛7鍙2/5锛7鍙3/5锛7鍙4/5锛7鍙3/4锛7鍙2/3銆傛湁6涓8+7+8+6+9+6=44涓
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