正三棱柱的底面边长是3,高为3,则体积是多少
\u6b63\u4e09\u68f1\u67f1\u7684\u5e95\u9762\u8fb9\u957f\u4e3a2\uff0c\u9ad8\u4e3a3\uff0c\u5219\u4f53\u79ef\u662f\u5e95\u9762\u79ef=\u6839\u53f73
\u4f53\u79ef=\u6839\u53f73\u00d73\u00d71/3=\u6839\u53f73
\u8865\u5145\uff1a\u5e95\u9762\u79ef
\u56e0\u4e3a\u662f\u6b63\u4e09\u68f1\u67f1\uff0c\u6240\u4ee5\u5e95\u9762\u662f\u6b63\u4e09\u89d2\u5f62\u5373\u7b49\u8fb9\u4e09\u89d2\u5f62
\u7b49\u8fb9\u4e09\u89d2\u5f62\u7684\u8fb9\u662f2
\u6240\u4ee5\uff0c\u5e95\u9762\u4e09\u89d2\u5f62\u7684\u9ad8\u662f\u6839\u53f73
\u6240\u4ee5\u5e95\u9762\u9762\u79ef\u662f\u6839\u53f73
\u6b63\u68f1\u67f1=2\u00d73\u00d72\u00f72=6(cm3)
2\u00d72\u00f72=2
\u5e95\u9762\u79ef \u00d7\u9ad8=3\u500d\u6839\u53f73
\u4fa7\u9762\u79ef\uff1a4x5x3=60
\u5168\u9762\u79ef\uff1a4x2\u500d\u6839\u53f7\u4e09x2x1/2=8\u500d\u6839\u53f7\u4e09
\u4f53\u79ef\uff1a4x2\u500d\u6839\u53f7\u4e09x1/2x5=20\u500d\u6839\u53f7\u4e09
\u4e0d\u4f1a\u6253\u6839\u53f7\uff0c\u62b1\u6b49
V=27√3/2
V=Sh=sqr(3)/4*9*3=sqr(3)*27/4
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绛旓細渚ч潰绉36骞虫柟鍘樼背锛屼綋绉3鏍瑰彿3绔嬫柟鍘樼背
绛旓細渚ч潰绉=3脳涓涓渚ч潰鐨勯潰绉=3脳锛3脳4锛=36 浣撶Н=S搴曢潰绉楅珮=锛1/2脳3^2脳sin60º锛壝4=9鈭3
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