王阿姨做了一个圆形的抱枕,长80厘米,底面直径18厘米,如果侧面用花布,底面用黄色的布,两种布各需 王阿姨做了一个圆柱形的抱枕,长80厘米,底面直径18厘米。如...
\u738b\u963f\u59e8\u505a\u4e86\u4e00\u4e2a\u5706\u67f1\u5f62\u7684\u62b1\u6795\uff0c\u957f80Cm\uff0c\u5e95\u9762\u76f4\u5f8418\u5398\u7c73\u3002\u5982\u679c\u4fa7\u9762\u7528\u82b1\u5e03\uff0c\u5e95\u9762\u7528\u9ec4\u8272\u7684\u5e03\uff0c\u4e24\u79cd\u5e03\u5404\u597d\u597d\u770b\u770b\u57fa\u672c\u516c\u5f0f\u5427
\u82b1\u5e03\u7684\u7528\u6599=\u5706\u67f1\u5f62\u7684\u4fa7\u9762\u79ef=\u03c0d*h=3.14*18*80=4521.6\u5e73\u65b9\u5398\u7c73
\u9ec4\u5e03\u7684\u7528\u6599=\u4e24\u4e2a\u5e95\u9762\u7684\u9762\u79ef\u548c=2*\u03c0r^2=2*3.14*9*9=508.68\u5e73\u65b9\u5398\u7c73
=侧面积
=3.14×18×80
=4521.6平方厘米
黄布用布
=底面积×2
=3.14×(18÷2)²×2
=508.68平方厘米
绛旓細=渚ч潰绉 =3.14脳18脳80 =4521.6骞虫柟鍘樼背 榛勫竷鐢ㄥ竷 =搴曢潰绉2 =3.14脳锛18梅2锛²脳2 =508.68骞虫柟鍘樼背
绛旓細鏁呯瓟妗堜负锛氳姳甯冿細4 521.6 cm 榛勫竷锛508.68 cm
绛旓細搴曢潰鍗婂緞锛18梅2=9锛堝帢绫筹級闇瑕侀粍甯冿細9²脳3.14脳2=508.68锛堝钩鏂瑰帢绫筹級闇瑕佽姳甯冿細18脳3.14脳80=4521.6锛堝钩鏂瑰帢绫筹級
绛旓細瑙o細榛勫竷闇瑕 3.14脳锛18梅2锛²脳2 =3.14脳81脳2 =508.68锛堝钩鏂瑰帢绫筹級鑺卞竷闇瑕 3.14脳18脳80 =56.52脳80 =4521.6锛堝钩鏂瑰帢绫筹級绛旓細闇瑕侀粍甯508.68骞虫柟鍘樼背锛岄渶瑕佽姳甯4521.6骞虫柟鍘樼背銆傜浣犲紑蹇
绛旓細r=18/2=9 搴曢潰绉=3.14*9*9*2=508.68 渚ч潰绉=3.14*18*80=4521.6
绛旓細涓銆佷晶闈㈣姳甯冪敤閲忎篃灏辨槸鍦嗘煴鐨勪晶闈㈢Н锛毾脳D脳h=3.14脳18脳80=4521.6骞虫柟鍘樼背锛涗簩銆佸簳闈㈤粍甯冪敤閲忎篃灏辨槸2鍊嶇殑鍦嗘煴搴曢潰绉細2脳蟺脳r^2=2脳3.14脳(18梅2)^2=508.68骞虫柟鍘樼背銆
绛旓細鑺卞竷瑕288蟺銕濈殑骞虫柟锛岄粍甯冭162蟺銕濈殑骞虫柟銆
绛旓細闀80cm锛屽绛変簬鍦嗘煴浣撳懆闀匡紝鍗18cm*3.1415926 鍒楀紡锛80*18*3.1415926=4523.893344骞虫柟鍘樼背 鍐嶆眰榛勫竷闈㈢Н锛屾湁涓や釜绔潰锛屾墍浠ラ粍甯冮潰绉槸鍦伴潰绉殑2鍊 鍒楀紡锛18/2*18/2*3.1415926*2 =9*9*3.1415926*2 =508.938骞虫柟鍘樼背 绛旓細闇鑺卞竷4523.893344骞虫柟鍘樼背锛岄渶榛勫竷508.938骞虫柟鍘樼背銆
绛旓細渚ч潰绉細2蟺rh=2脳3.14脳9脳80=4521.6 骞虫柟鍘樼背 鑺卞竷瑕佺敤4521.6 骞虫柟鍘樼背 搴曢潰绉細2蟺r²=2脳3.14脳81=508.68骞虫柟鍘樼背 榛勫竷瑕佺敤508.68骞虫柟鍘樼背
绛旓細鑺卞竷锛3.14x18x80=4521.6骞虫柟鍘樼背 榛勫竷锛18梅2=9cm 3.14x9x9x2=508.68骞虫柟鍘樼背