<span id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<thead id="bprf1"><noframes id="bprf1">
<span id="bprf1"><video id="bprf1"></video></span>
<th id="bprf1"><noframes id="bprf1"><span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<progress id="bprf1"><video id="bprf1"></video></progress>
<span id="bprf1"></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike><strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span><strike id="bprf1"><video id="bprf1"></video></strike>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"></video></span><th id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></th>
<ruby id="bprf1"><dl id="bprf1"><del id="bprf1"></del></dl></ruby>
<strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"></span>
<th id="bprf1"></th>
<span id="bprf1"></span>
<strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"><video id="bprf1"></video></span>
<address id="bprf1"></address>
<th id="bprf1"><video id="bprf1"></video></th><th id="bprf1"><video id="bprf1"></video></th>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<del id="bprf1"><i id="bprf1"><del id="bprf1"></del></i></del>
<th id="bprf1"></th><noframes id="bprf1"><menuitem id="bprf1"><var id="bprf1"></var></menuitem><strike id="bprf1"></strike><span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span><strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></th><progress id="bprf1"></progress><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<span id="bprf1"></span><th id="bprf1"></th>
<span id="bprf1"></span>
<th id="bprf1"><noframes id="bprf1"><strike id="bprf1"><video id="bprf1"></video></strike><th id="bprf1"></th>
<th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"></video></span><strike id="bprf1"></strike>
<span id="bprf1"><noframes id="bprf1"><strike id="bprf1"></strike>
<menuitem id="bprf1"><ins id="bprf1"></ins></menuitem>
<span id="bprf1"></span>
<video id="bprf1"><listing id="bprf1"><thead id="bprf1"></thead></listing></video>
您的位置: 范文大全 > 学习资料 > 关于有理数的混合运算测试及答案的范文

有理数的混合运算测试及答案

来源qc99范文网 | 发布2017-09-27 08:31

   有理数的混合运算法则与小学所学的“数的混合运算法则”基本相同.即?#21512;?#20056;方开方、再乘除、后加减、有括号先算括号内.只是在加减混合运算中,把减法统一成加法来作.

  有理数的混合运算

  教学目标

  1.进一步掌握有理数的运算法则和运算律;

  2.使学生能够熟练地按有理数运算顺序进行混合运算;

  3.注意培养学生的运算能力.

  教学重点和难点

  重点有理数的混合运算.

  难点准确地掌握有理数的运算顺序和运算中的符号问题.

  课堂教学过程设计

  一、从学生原有认知结构提出问题

  1.计算(五分钟练习)

  (5)-252; (6)(-2)3;(7)-7+3-6; (8)(-3)×(-8)×25;

  (13)(-616)÷(-28); (14)-100-27; (15)(-1)101; (16)021;

  (17)(-2)4; (18)(-4)2; (19)-32; (20)-23;

  (24)3.4×104÷(-5).

  2.说一说我们学过的有理数的运算律

  加法交换律a+b=b+a;

  加法结合律(a+b)+c=a+(b+c);

  乘法交换律ab=ba;

  乘法结合律(ab)c=a(bc);

  乘法分配律a(b+c)=ab+ac.

  二、讲授新课

  前面我们已经学习了有理数的加、减、乘、除、乘方等运算若在一个算式里含有以上的混合运算按怎样的顺序进行运算?

  1.在只有加减或只有乘除的同一级运算中按照式子的顺序从左向右?#26469;?#36827;行.

  审题(1)运算顺序如何?

  (2)符号如何?

  说明含有带分数的加减法方法是将整数部分和分数部分相加再计算结果.带分数分成整数部分和分数部分时的符号与原带分数的符号相同.

  课堂练习

  审题运算顺序如何?#33539;?

  注意结果中的负号不能丢.

  课堂练习

  计算(1)-2.5×(-4.8)×(0.09)÷(-0.27);

  2.在没有括号的不同级运算中先算乘方再算乘除最后算加减.

  例3 计算

  (1)(-3)×(-5)2; (2)[(-3)×(-5)]2;

  (3)(-3)2-(-6); (4)(-4×32)-(-4×3)2.

  审题运算顺序如何?

  解(1)(-3)×(-5)2=(-3)×25=-75.

  (2)[(-3)×(-5)]2=(15)2=225.

  (3)(-3)2-(-6)=9-(-6)=9+6=15.

  (4)(-4×32)-(-4×3)2

  =(-4×9)-(-12)2

  =-36-144

  =-180.

  注意搞清(1)(2)的运算顺序(1)中先乘方再相乘(2)中先计算括号内的然后再乘方.(3)中先乘方再相减(4)中的运算顺序要分清第一项(-4×32)里先乘方再相乘第二项(-4×3)2中小括号里先相乘再乘方最后相减.

  课堂练习

  计算

  (1)-72; (2)(-7)2; (3)-(-7)2;

  (7)(-8÷23)-(-8÷2)3.

  例4 计算

  (-2)2-(-52)×(-1)5+87÷(-3)×(-1)4.

  审题(1)存在哪几级运算?

  (2)运算顺序如何?#33539;?

  解 (-2)2-(-52)×(-1)5+87÷(-3)×(-1)4

  =4-(-25)×(-1)+87÷(-3)×1(先乘方)

  =4-25-29(再乘除)

  =-50.(最后相加)

  注意(-2)2=4-52=-25(-1)5=-1(-1)4=1.

  课堂练习

  计算

  (1)-9+5×(-6)-(-4)2÷(-8);

  (2)2×(-3)3-4×(-3)+15.

  3.在带有括号的运算中先算小括号再算中括号最后算大括号.

  课堂练习

  计算

  三、小结

  教师引导学生一起总结有理数混合运算的规律.

  1.先乘方再乘除最后加减;

  2.同级运算从左到右按顺序运算;

  3.若有括号先小再中最后大?#26469;?#35745;算.

  四、作业

  1.计算

  2.计算

  (1)-8+4÷(-2); (2)6-(-12)÷(-3);

  (3)3·(-4)+(-28)÷7; (4)(-7)(-5)-90÷(-15);

  3.计算

  4.计算

  (7)1÷(-1)+0÷4-(-4)(-1);(8)18+32÷(-2)3-(-4)2×5.

  5*.计算(题中的字母均为自然数)

  (1)(-12)2÷(-4)3-2×(-1)2n-1;

  (4)[(-2)4+(-4)2·(-1)7]2m·(53+35).

  有理数的混合运算

  #随堂检测

  1、 下列计算正确的是( )

  2、计算 等于( )

  A. 4 B. 5 C. 3 D.-16

  3、高度每增加1km气温大约降低60C观测的气球的温度是-370C地面温度是50C则气球高度大约是________km

  4、计算 =________

  5、计算 _______

  6、计算

  #典例分析

  计算

  含有多种括号去括号的一般方法是由内向外?#26469;?#21435;掉小、?#23567;?#22823;括号;?#37096;?#20197;由外到内去括号去大括号时把中括号看成一个整体去中括号时把小括号看做一个整体最后去掉小括号。

  解

  #课下作业

  ¢拓展提高

  1、若四个有理数之和的 ( )

  A -9 B 15 C -18 D 21

  2、若x是有理数则x2+1的值一定是( )

  A 等于1 B 大于1 C 不小于1 D非负数

  3、算式22+22+22+22可化为( )

  A 24 B 28 C 82 D 216

  4、计算(1)

  (2)

  5、用简便方法计算

  6、创新题小王的 电脑中设置了一个关于有理数的运算程序输入a加“*”键再输入数b得到运算a*b=a2-2

  ¢ 体验中考

  1、(2009,孝感)在算式 中的()所在位置填入下列哪种运算负号计算出来的值最小( )

  A.+ B.– C.× D.

  2、(2009年台湾) 计算127(32)16(4)之值为何?

  A.36 B.164 C.216 D. 232

  参考答案

  #随堂检测

  1、D

  2、B =1+22=5

  3、7 由题意可列式得[5-(-37)]

  4、-1 =-9÷9=-1

  5、 (-1)×(-3)×3=9

  6、

  # 课下作业

  ¢拓展提高

  1、D 由题意得四个有理数之和为12所以第四个数为12-[(-12)+(-6)+9]=21

  2、C 因为x是有理数所以x2不小于0则x2+1不小于1.

  3、A 因为22+22+22+22=4×22=24

  4、(1) =-6-30=-36

  (2)

  5、

  6、

  ¢体验中考

  1、C

  2、D

http://www.wleo.tw/book/ziliao/222691.html 为您分享.
上一篇性格决定命运 下一篇没有了
专题范文
大家都在看
娱?#20013;?#38395;
<span id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<thead id="bprf1"><noframes id="bprf1">
<span id="bprf1"><video id="bprf1"></video></span>
<th id="bprf1"><noframes id="bprf1"><span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<progress id="bprf1"><video id="bprf1"></video></progress>
<span id="bprf1"></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike><strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span><strike id="bprf1"><video id="bprf1"></video></strike>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"></video></span><th id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></th>
<ruby id="bprf1"><dl id="bprf1"><del id="bprf1"></del></dl></ruby>
<strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"></span>
<th id="bprf1"></th>
<span id="bprf1"></span>
<strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"><video id="bprf1"></video></span>
<address id="bprf1"></address>
<th id="bprf1"><video id="bprf1"></video></th><th id="bprf1"><video id="bprf1"></video></th>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<del id="bprf1"><i id="bprf1"><del id="bprf1"></del></i></del>
<th id="bprf1"></th><noframes id="bprf1"><menuitem id="bprf1"><var id="bprf1"></var></menuitem><strike id="bprf1"></strike><span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span><strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></th><progress id="bprf1"></progress><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<span id="bprf1"></span><th id="bprf1"></th>
<span id="bprf1"></span>
<th id="bprf1"><noframes id="bprf1"><strike id="bprf1"><video id="bprf1"></video></strike><th id="bprf1"></th>
<th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"></video></span><strike id="bprf1"></strike>
<span id="bprf1"><noframes id="bprf1"><strike id="bprf1"></strike>
<menuitem id="bprf1"><ins id="bprf1"></ins></menuitem>
<span id="bprf1"></span>
<video id="bprf1"><listing id="bprf1"><thead id="bprf1"></thead></listing></video>
采臼11x5恠米夕
<span id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<thead id="bprf1"><noframes id="bprf1">
<span id="bprf1"><video id="bprf1"></video></span>
<th id="bprf1"><noframes id="bprf1"><span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<progress id="bprf1"><video id="bprf1"></video></progress>
<span id="bprf1"></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike><strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span><strike id="bprf1"><video id="bprf1"></video></strike>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"></video></span><th id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></th>
<ruby id="bprf1"><dl id="bprf1"><del id="bprf1"></del></dl></ruby>
<strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"></span>
<th id="bprf1"></th>
<span id="bprf1"></span>
<strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"><video id="bprf1"></video></span>
<address id="bprf1"></address>
<th id="bprf1"><video id="bprf1"></video></th><th id="bprf1"><video id="bprf1"></video></th>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<del id="bprf1"><i id="bprf1"><del id="bprf1"></del></i></del>
<th id="bprf1"></th><noframes id="bprf1"><menuitem id="bprf1"><var id="bprf1"></var></menuitem><strike id="bprf1"></strike><span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span><strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></th><progress id="bprf1"></progress><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<span id="bprf1"></span><th id="bprf1"></th>
<span id="bprf1"></span>
<th id="bprf1"><noframes id="bprf1"><strike id="bprf1"><video id="bprf1"></video></strike><th id="bprf1"></th>
<th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"></video></span><strike id="bprf1"></strike>
<span id="bprf1"><noframes id="bprf1"><strike id="bprf1"></strike>
<menuitem id="bprf1"><ins id="bprf1"></ins></menuitem>
<span id="bprf1"></span>
<video id="bprf1"><listing id="bprf1"><thead id="bprf1"></thead></listing></video>
<span id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<thead id="bprf1"><noframes id="bprf1">
<span id="bprf1"><video id="bprf1"></video></span>
<th id="bprf1"><noframes id="bprf1"><span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"></video></span>
<progress id="bprf1"><video id="bprf1"></video></progress>
<span id="bprf1"></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike><strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span><strike id="bprf1"><video id="bprf1"></video></strike>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"></video></span><th id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></th>
<ruby id="bprf1"><dl id="bprf1"><del id="bprf1"></del></dl></ruby>
<strike id="bprf1"><video id="bprf1"></video></strike>
<span id="bprf1"></span>
<th id="bprf1"></th>
<span id="bprf1"></span>
<strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"></span>
<strike id="bprf1"></strike>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<span id="bprf1"><video id="bprf1"></video></span>
<address id="bprf1"></address>
<th id="bprf1"><video id="bprf1"></video></th><th id="bprf1"><video id="bprf1"></video></th>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<del id="bprf1"><i id="bprf1"><del id="bprf1"></del></i></del>
<th id="bprf1"></th><noframes id="bprf1"><menuitem id="bprf1"><var id="bprf1"></var></menuitem><strike id="bprf1"></strike><span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><dl id="bprf1"><ruby id="bprf1"></ruby></dl></span>
<span id="bprf1"><video id="bprf1"></video></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span><strike id="bprf1"><video id="bprf1"><ruby id="bprf1"></ruby></video></strike><th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"><span id="bprf1"></span></video></th><progress id="bprf1"></progress><th id="bprf1"></th>
<span id="bprf1"></span>
<span id="bprf1"><video id="bprf1"><strike id="bprf1"></strike></video></span>
<th id="bprf1"><video id="bprf1"></video></th>
<span id="bprf1"></span>
<span id="bprf1"></span><th id="bprf1"></th>
<span id="bprf1"></span>
<th id="bprf1"><noframes id="bprf1"><strike id="bprf1"><video id="bprf1"></video></strike><th id="bprf1"></th>
<th id="bprf1"></th>
<span id="bprf1"><video id="bprf1"></video></span><strike id="bprf1"></strike>
<span id="bprf1"><noframes id="bprf1"><strike id="bprf1"></strike>
<menuitem id="bprf1"><ins id="bprf1"></ins></menuitem>
<span id="bprf1"></span>
<video id="bprf1"><listing id="bprf1"><thead id="bprf1"></thead></listing></video>