1112a)(xyxyxxyxyx522)(xyxyyx)4(aaa13((11))001aa)2(1aa)3(21)4(2)5(计算:计算:4x4x2xx2x3322再来试试1124744312xxxyxyxyyxyxx2)1(1x1)2()2x(x3x)3(计算:4122bbababa先乘方;再乘除;最后加减;先乘方;再乘除;最后加减;有括号先做括号内.有括号先做括号内.分式的混合运算顺序:解:4122bbabababbababa41422)()(4)(44)(4222222babbaabababababa2222244444()()aaababababbababb1、2、xyyxxyyx22222211111212xxxxxx计算:试一试423y8x4xy)1(1x2x4x4)2(221111)1(2xxxxxxxxxxx4)44122)(2(22nmmnmnmm2121)3(再来试试1x)1(2)2x(1)2(1)3(1.2.3.4.1.2.3.4.aaaaaaaaa2444122222)225(423xxxxxxxxxxxx42442221a1a1a1a1a2aa8a42)()(5.6.5.6.xxxxxx24222122412232aaaa2x1.1)6a)(2a(6a15.2xyxyxxyxyxx32327、1.解法一:1.解法一:aaaaaaaa42)2()1(4222aaaaaa4)2()2(4221aaaaaaaaaa24441222221.解法二:1.解法二:aaaaaaaaaaaa424414222222221aaaaaaaaaa2444122222aaaaaa42142=……2.解:2)2)(2(5423xxxxx292423xxxx)3(21x)225(423xxxxxxxxx)2)(2(2121xxxxxxxx)2)(2()2(1)2)(2()2(1xxxx22x43.解:xxxxxxxx42442224.解:)1)(1(4)1)(2()2(4aaaaaaaaaaaa4)1)(1()1(41a111112842aaaaaaaa)()(仔细观察题目的结构特点,灵活运用运算律,适当运用计算技巧,可简化运算,提高速度,优化解题。分式的混合运算:关键是要正确的使用相应的运算法则和运算顺序;正确的使用运算律,尽量简化运算过程;结果必须化为最简分式。混合运算的特点:是整式运算、因式分解、分式运算的综合运用,综合性强。xyxyxxyxyxx3232例2.计算:1.解:原式解:原式yxxyxxyxyxx)(3232yxx2yxx2巧用分配律yxxxx131232babababa11)(1)(122把和看成整体,题目的实质是平方差公式的应用。ba1ba1例3.计算:巧用公式解:babababababa111111baba11babababa11)(1)(122222baa繁分式的化简:1.把繁分式转化成分子除以分母的形式,利用除法法则化简;2.利用分式的基本性质化简。