--1--目录第一部分——温故知新专题一整式运算·················································1专题二乘法公式·················································3专题三平行线的性质与判定·······································9专题四三角形的基本性质·········································11专题五全等三角形···············································14专题六如何做几何证明题·········································17专题七轴对称···················································22第二部分——提前学习专题一勾股定理·················································25专题二平方根与算数平方根·······································29专题三立方根···················································32专题四平方根与立方根的应用····································35专题五实数的分类···············································39专题六最简二次根式及分母有理化··································42专题七非负数的性质及应用·······································46专题八二次根式的复习···········································49-1-第一部分——温故知新专题一整式运算1.由数字与字母组成的代数式叫做单项式。单独一个数或字母也是单项式。单项式中的叫做单项式的系数单项式中所有字母的叫做单项式的次数2.几个单项式的和叫做多项式多项式中叫做这个多项式的次数3.单项式和多项式统称为4.整式加减实质就是后5.同底数幂乘法法则:nmnmaaa·(m.n都是正整数);逆运算nma6.幂的乘方法则:nma(m.n都是正整数);逆运算mna7.积的乘方法则:nab(n为正整数);逆运算nnba8.同底数幂除法法则:nmnmaaa(a≠0,m.n都是正整数);逆运算nma9.零指数的意义:010aa;10.负指数的意义:为正整数paaapp,0111.整式乘法:(1)单项式乘以单项式;(2)单项式乘以多项式;(3)多项式乘以多项式12.整式除法:(1)单项式除以单项式;(2)多项式除以单项式知识点1.单项式多项式的相关概念归纳:在准确记忆基本概念的基础上,加强对概念的理解,并灵活的运用例1.下列说法正确的是()A.没有加减运算的式子叫单项式B.35ab的系数是35C.单项式-1的次数是0D.3222abba是二次三项式例2.如果多项式1132xnxm是关于x的二次二项式,求m,n的值知识点2.整式加减归纳:正确掌握去括号的法则,合并同类项的法则例3.多项式8313322xyykxyx中不含xy项,求k的值知识点3.幂的运算-2-归纳:幂的运算一般情况下,考题的类型均以运算法则的逆运算为主,加强对幂的逆运算的练习,是解决这类题型的核心方法。例4.已知5,3nmaa求(1)nma32的值(2)nma23的值例5.计算(1)20102011324143(2)1012201021知识点4.整式的混合运算归纳:整式的乘法法则和除法法则是整式运算的依据,注意运算时灵活运用法则。例6.先化简,再求值:bababbabba3222,其中1,21ba知识点5.运用幂的法则比较大小归纳:根据幂的运算法则,可以将比较大小的题分为两种:①化为同底数比较;②化为同指数比较例7.比较大小(1)3344555,4,3cba(2)25314132,16,8cba1.若A是五次多项式,B是三次多项式,则A+B一定是()A.五次整式B.八次多项式C.三次多项式D.次数不能确定2.已知3181a,4127b,619c,则a、b、c的大小关系是()A.a>b>cB.a>c>bC.a<b<cD.b>c>a3.若142yx,1327xy,则yx等于()A.-5B.-3C.-1D.14.下列叙述中,正确的是()A.单项式yx2的系数是0,次数是3B.a、π、0、22都是单项式C.多项式12323aba是六次三项式D.2nm是二次二项式5.下列说法正确的是()A.任何一个数的0次方都是1B.多项式与多项式的和是多项式C.单项式与单项式的和是多项式D.多项式至少有两项6.下列计算:①0(1)1②1(1)1③21222④2213(0)3aaa⑤22()()mmaa⑥32321aaaa正确的有()A.2个B.3个C.4个D.5个7.在yxyax与3的积中,不想含有xy项,则a必须为.8.若qaapaa3822中不含有23aa和项,则p,q.9.比较大小(1)11142081,27,9cba(2)751003,2ba(3)1220245,4,2cba-3-10.计算(1)31022122(2)20062005532135专题二乘法公式1.平方差公式:22bababa平方差公式的一些变形:(1)位置变化:abba22ba(2)系数变化:baba535322259ba(3)指数变化:2323nmnm46nm(4)符号变化:baba=2222abba(5)数字变化:98×102=(100-2)×(100+2)=10000-4=9996(6)增项变化:zyxzyx222222yzxzxyzx(7)增因式变化:4422224422bababababababa88ba2.完全平方公式:2222222,2babababababa完全平方公式的一些变形:(1)形如2cba的计算方法2cba222222222cbcacbabaccbaba(2)完全平方公式与平方差公式的综合运用cbacba2222222242cbcbacba(3)幂的运算与公式的综合运用2222baba42242228164bbaaba(4)利用完全平方公式变形,求值是一个难点。已知:求的值,,abba:abbaba422,abbaba2222已知:求的值,,abba:abbaba422,abbaba2222-4-已知:求的值,,22baba:2222babaab已知:求的值或,,,22babababa:422babaab(5)运用完全平方公式简化复杂的运算9980011200010000001100099922知识点1.平方差公式的应用例1.计算下列各题(1)yxyx2131213122(2)byaxbyax(3)999×1001例2.计算(1)112121212200642(2)20132011201220122知识点2.完全平方公式例3.计算(1)222121yxyx(2)cbacba22例4.已知.1,3abba求(1)22ba(2)2ba例5.已知1,5yxyx,求xy的值知识点3.配完全平方式归纳:配完全平方式求待定系数有三种情况,求一次项系数(2个答案)求另一个平方项(1个答案)求另一个平方项的底数(2个答案)例6.已知mxx842是一个完全平方式,则m的值为()A.2B.2C.4D.4知识点4.技巧性运算归纳:观察规律,找突破口,准确判断是添项还是拆项,熟记常见题型例6.(1-21)(1+21)(1-31)(1+31)(1-41)(1+41)···(1-101)(1+101)例7.(1-221)(1-231)(1-241)···(1-291)(1-2101)例8.(1+21)(1+221)(1+421)(1+821)(1+1621)(1+3221)例9.19902-19892+19882-19872···+22-1-5-1.已知m+n=2,mn=-2,则m²+n²的值为()A.4B.2C.16D.82.若n为正整数,且72nx,则nnxx2223)(4)3(的值为()A.833B.2891C.3283D.12253.若2ba,1ca,则22)()2(accba等于()A.9B.10C.2D.14.下列说法正确的是()A.2x-3的项是2x,3B.x-1和1x-1都是整式C.x2+2xy+y2与5xy都是多项式D.3x2y-2xy+1是二次三项式5.若单项式3xmy2m与-2x2n-2y8的和仍是一个单项式,则m,n的值分别是()A.1,5B.5,1C.3,4D.4,36.下列多项式中是完全平方式的是()A.2x2+4x-4B.16x2-8y2+1C.9a2-12a+4D.x2y2+2xy+y27.若a-1a=2,则a2+21a的值为()A.0B.2C.4D.68.如果多项式92mxx是一个完全平方式,则m的值是()A.±3B.3C.±6D.69.248323(21)(21)(21)(21)1的个位数字为()A.2B.4C.6D.810.下列叙述中,正确的是()A.单项式yx2的系数是0,次数是3B.a、π、0、22都是单项式C.多项式12323aba是六次三项式D.2nm是二次二项式11.下列说法正确的是()A.任何一个数的0次方都是1B.多项式与多项式的和是多项式C.单项式与单项式的和是多项式D.多项式至少有两项12.下列计算:①0(1)1②1(1)1③21222④2213(0)3aaa⑤22()()mmaa⑥32321aaaa正确的有()A.2个B.3个C.4个D.5个13.已知,x、y是非零数,如果5yxxy,则______________11yx.14._________________4422babababa.-6-15.乘积2222200011411311211219991-1=______________.16.若))(3(152nxxmxx,则m=.17.已知12,3abba,则22baba=__________2)(ba=__________.18.已知71122baba,,则ab的值是.19.已知2131xxxx,则的值为.20.已知2235baabba,则,的值为.21.当x=,y=时,多项式11249422yxy