1、单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,组合体的体积,40cm,40cm,9cm,9cm,72cm,30cm,30cm,同桌讨论,尝试解答,8cm,9cm,40cm,72cm,10cm,8cm,a,b,c,解:,V a,abh,9408,2880,(,cm,3,),Va =Vb,Va+Vb=28802=5760,(,cm,3,),V c,abh,72108,5760,(,cm,3,),5760+5760=11520,(,cm,3,),答:这个铸铁零件的体积是,11520,立方厘米,。,8cm,9cm,30cm,8cm,10cm,a,b,c,解
2、V a,abh,9308,2160,(,cm,3,),Va=Vb,Va+Vb=21602=4320,(,cm,3,),Vc,abh,(72+9+9)108,90108,7200,(,cm,3,),72+9+9,90cm,4320+7200=11520,(,cm,3,),答:这个铸铁零件的体积是,11520,立方厘米,。,a,解:,Va,abh,(72+9+9),40,8,90,40,8,28800,(,cm,3,),b,Vb,abh,72,30,8,17280,(,cm,3,),28800-17280=11520,(,cm,3,),答:这个铸铁零件的体积是,11520,立方厘米。,30,2
3、0,26,9,试一试:求下列组合体的体积,(,单位:,cm,),(1),10,25,14,6,4,11,(2),a,b,a,b,解:,Va,abh,(30-9),10,26,27,10,26,7020,(,cm,3,),Vb,abh,9,20,26,4680,(,cm,3,),7020+4680=11700,(,cm,3,),答:这个组合体的体积是,11700 cm,3,。,解:,Va,abh,6,14,11,924,(,cm,3,),Vb,abh,25,14,4,1400,(,cm,3,),924+1400=2324,(,cm,3,),答:这个组合体的体积是,2324 cm,3,。,求下列组
4、合体的体积,(,单位:,dm,),(3),42,38,16,14,30,a,b,解:,Va,abh,42,30,38,47880,(,dm,3,),Vb,abh,14,30,16,6720,(,dm,3,),47880-6720=41160,(,dm,3,),答:这个组合体的体积是,41160 dm,3,。,拓展练习,求组合体的体积,120cm,80cm,82cm,25cm,30cm,60cm,a,b,解:,Va,abh,120,60,80,576000,(,cm,3,),Vb,abh,82,(60-30),25,82,30,25,61500,(,cm,3,),576000-61500=514500,(,cm,3,),答:这个组合体的体积是,514500 cm,3,。,