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来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/25 04:33:37
 
<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"">上面一道题,我的结果是:-7<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"">或3<span style="font-family:
宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"">或9<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"">或19<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"">,但书后面的答案为:-7<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"">或3<span style="font-family:
宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"">(只给了答案,没有过程).我不知道为什么9<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"">或19<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"">这两个结果不行.
 
<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"">下面一道计算题,书也只给了答案,
<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"">注:每个括号里,1<span style="font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"">后面都是+<span style="font-family:
宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"">号(摄像头拍的,不是特别清楚).
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宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"">


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宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"">

 

在word上写好复制过来,发出来想不到一堆乱码,好像也没有重新编辑的功能,只好补充说明一下:
我的结果是:-7或3或9或19,但答案为-7或3,不知道9或19为啥不行?
注:每个括号里,1后面都是+号。
第一题:数轴上,点B表示6,AB=8,AP=5.情况有四种.B=6,A在B的左侧时,那么A=-2,若P也在A的左侧,那么P 所表示的就是-7 ;若P在A的右侧,那么P表示的就是3.B=6,A在B的右侧时,A= 14,若P 在A的左侧,那么P表示的就是9;若P在A的右侧,那么P表示的就是19.
按道理,9或19应该是可以的.只能说题目出的不够仔细.
第二题:把1化到分子里,得到,(1*3+1)/(1*3)*(2*4+1)/(2*4)*(3*5+1)/(3*5)*...*(97*99+1)/(97*99)*(98*100+1)/(98*100)
=2的平方/(1*3)*3的平方/(2*4)*4的平方/((3*5)*...*98的平方/(97*99)*99的平方/(98*100)
分子分母约掉之后,分子剩下2*99,分母则是100.99/50= 1.98