资源描述
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,*,*,角度的运算,淮滨一中 张世宇,30,、,45,、,60,、,90,、,15,、,75,、,105,、,120,、,135,、,150,、,165,试一试：,一副三角板可以拼成多少度的角？（,0,度和,180,度除外,）,角的度量单位：度、分、秒,.,度,分,秒,60,60,3600,60,3600,60,1,的,60,分之一为,1,分，记作“,1”,，即,1,60,1,的,60,分之一为,1,秒，记作“,1”,，即,1,60,回顾：角的度量单位,填空,（,1,）,34.5,0,=,0,/,（,2,）,112.27,0,=,0,/,/,解：（,1,）,34.5,0,=34,0,+0.5,0,=34,0,+0.5,60,/,=34,0,+3 0,/,=34,0,30,/,（,2,）,112.27,0,=112,0,+0.2760,/,=112,0,+16.2,/,=112,0,+16,/,+0.260,/,=112,0,16,/,12,/,34,30,112,16,12,复习：,把下列各题结果化成度,72,0,36,/,(2)37,0,14,/,24,/,解,:(1)72,0,36,/,=72,0,+36,/,=72,0,+(3660),0,=72,0,+0.6,0,=72.6,0,复习：,(2)37,0,14,/,24,/,=37,0,+14,/,+24,/,=37,0,+14,/,+(24,60),/,=37,0,+14,/,+0.4,/,=37,0,+14.4,/,=37,0,+(14.460),0,=37,0,+0.24,0,=37.24,0,复习：,例,1,、加减法计算,解,:(1),原式,=(12+45),0,+(36+24),/,+(56+35),/,=57,0,+60,/,+91,/,=57,0,+61,/,+31,/,=58,0,+1,/,+31,/,=58,0,1,/,31,/,角度的加减法运算,(1)12,0,36,/,56,/,+45,0,24,/,35,/,(2)79,0,45,/,61,0,48,/,49,/,(2)79,0,45,/,61,0,48,/,49,/,解,:,原式,=79,0,44,/,60,/,61,0,48,/,49,/,=78,0,104,/,60,/,61,0,48,/,49,/,=(78-61),0,(104-48),/,(60-49),/,=17,0,56,/,11,/,例,2,、乘除法运算,(3)21,0,31,/,27,/,3 (4)63,0,21,/,39,/,3,(5)106,0,6,/,25,/,5,解,:,原式,=(213),0,(313),/,(273),/,=63,0,93,/,81,/,=63,0,94,/,21,/,=64,0,34,/,21,/,角度的乘除法,(4)63,0,21,/,39,/,3,解,:,原式,=(633),0,(213),/,(393),/,=21,0,7,/,13,/,(5)106,0,6,/,25,/,5,解,:,原式,=(1065),0,(65),/,(255),/,=21,0,(,66,5),/,(255),/,=21,0,13,/,(,85,5),/,=21,0,13,/,17,/,题型三：角度的乘除法运算,计算,练习,=825936,解（,1,）,=3738+4521.6,=3738+452136,解,=3236,=4660-1424,=,（,46-14,）,（,60-24,）,=,（,37+45,）,（,38+21,）,36,小结与归纳,1,度、分、秒都是,60,进制，逢,60,进,1,；,加减法要将度与度、分与分、秒与秒分别加减，,分秒相加逢,60,要进位，相减时要借,1,当作,60,；,（借,1,作,60,；借,1,作,60,）,3,乘法运算度分秒同时分别乘；,除法先从度开始除，除不尽转化为分，再,除不尽转化为秒，直到精确到要求的位数为止；,
展开阅读全文