1 00:00:00,540 --> 00:00:04,565 在上次的视频中,我们学习了从1至9的乘法口诀表 2 00:00:04,565 --> 00:00:06,960 可是上次我演示的时间不够了,不过,其实这是个好事情 3 00:00:06,960 --> 00:00:11,266 因为从1到9是乘法口诀表的核心基础 4 00:00:11,266 --> 00:00:14,702 不难看出,如果你掌握了从1到9的乘法口诀表 5 00:00:14,702 --> 00:00:16,720 那么用1和9之间的任何数字 6 00:00:16,720 --> 00:00:18,816 乘以1和9之间的任何数字 7 00:00:18,816 --> 00:00:21,670 你就能轻易的用乘法算出结果 8 00:00:21,670 --> 00:00:22,642 可是我现在想演示的是 9 00:00:22,642 --> 00:00:29,810 来做完10,11和12的乘法口诀表 10 00:00:29,820 --> 00:00:33,680 那么,什么是10乘以--让我们从数字0开始 11 00:00:33,680 --> 00:00:35,980 10乘以0 12 00:00:35,990 --> 00:00:39,030 任何数字乘以0都等于0 13 00:00:39,030 --> 00:00:40,375 10次0相加还是等于0 14 00:00:40,375 --> 00:00:43,933 0+0+0。。加10次还是等于10 15 00:00:43,933 --> 00:00:46,107 10乘1等于多少呢? 16 00:00:46,122 --> 00:00:48,034 10乘以1 17 00:00:48,034 --> 00:00:49,982 好,这个就是1次数字10 18 00:00:49,990 --> 00:00:52,740 或者是10次数字1相加 19 00:00:52,750 --> 00:00:53,890 等于10 20 00:00:53,890 --> 00:00:56,490 我觉得在这点上不需要我多说你就能算出来 21 00:00:56,500 --> 00:00:58,447 10乘2得多少呢? 22 00:00:58,447 --> 00:00:59,961 10乘以2 23 00:00:59,961 --> 00:01:02,660 我该换一个颜色写这个,但是我忘啦 24 00:01:02,670 --> 00:01:04,060 10乘以2 25 00:01:04,060 --> 00:01:08,950 等于10加10,也就是20 26 00:01:08,950 --> 00:01:09,550 很好 27 00:01:09,560 --> 00:01:12,650 注意,从上面开始,我们第一次结果得到一个10 28 00:01:12,650 --> 00:01:15,210 我们从这再一次得到一个20 29 00:01:15,210 --> 00:01:17,690 那么10乘3得多少呢? 30 00:01:17,700 --> 00:01:20,546 嗯,这个就是10加10再加10 31 00:01:20,546 --> 00:01:24,539 或者我们可以把这个看成是10乘2再加上一个10 32 00:01:24,539 --> 00:01:26,485 结果等于30 33 00:01:26,485 --> 00:01:27,385 10乘4呢? 34 00:01:27,385 --> 00:01:28,670 我希望你注意到了这个规律 35 00:01:28,680 --> 00:01:32,450 10乘4等于40 36 00:01:32,450 --> 00:01:37,400 看到这了吧,10乘以4就等于“4-0” 37 00:01:37,400 --> 00:01:42,030 如果我问来你,10乘以--- 38 00:01:42,040 --> 00:01:44,860 让我来还一个颜色--5? 39 00:01:44,870 --> 00:01:50,260 好吧,结果是50 40 00:01:50,260 --> 00:01:56,410 10乘以任何数字,得到的结果就是任何数字后面加一个0 41 00:01:56,410 --> 00:01:57,702 那么10的乘法口诀表 42 00:01:57,702 --> 00:01:59,315 你几乎就不用怎么死记硬背 43 00:01:59,315 --> 00:02:01,378 好,咱们接着往下继续 44 00:02:01,378 --> 00:02:04,109 10乘6得多少呢? 45 00:02:04,109 --> 00:02:06,840 结果就是--6-0! 46 00:02:06,840 --> 00:02:08,340 6-0 47 00:02:08,340 --> 00:02:11,090 10乘7呢? 48 00:02:11,090 --> 00:02:12,315 70 49 00:02:12,315 --> 00:02:13,340 10乘8? 50 00:02:13,340 --> 00:02:14,920 这个太好笑了 51 00:02:14,930 --> 00:02:16,810 10乘以8等于80 52 00:02:16,810 --> 00:02:19,020 10乘9呢? 53 00:02:19,030 --> 00:02:20,315 90 54 00:02:20,315 --> 00:02:21,590 10乘10呢? 55 00:02:21,590 --> 00:02:23,708 哦现在这个才有意思 56 00:02:23,708 --> 00:02:26,882 10乘10,也就是这个10-- 57 00:02:26,882 --> 00:02:29,523 让我来写清楚一下 58 00:02:29,523 --> 00:02:32,180 我来换一种橘色来写 59 00:02:32,180 --> 00:02:33,302 10乘10 60 00:02:33,302 --> 00:02:38,571 也就是10-0,或者说10后面加一个0 61 00:02:38,571 --> 00:02:41,702 就是这样的。看到了吧,无论什么数字乘以10,就在数字后面加一个0 62 00:02:41,702 --> 00:02:42,725 就得到了这个乘法结果 63 00:02:42,725 --> 00:02:43,950 所以这是100 64 00:02:43,960 --> 00:02:45,520 同时我希望你明白了为什么这个结果等于这个数 65 00:02:45,530 --> 00:02:47,900 我就是把10这个数字加了10遍 66 00:02:47,900 --> 00:02:51,700 那么每一个10,你从10,20,30依次算得的 67 00:02:51,710 --> 00:02:54,240 30也就相当于3个10相加或者10个3相加 68 00:02:54,250 --> 00:02:58,250 90也是10个9相加,或者9个10相加 69 00:02:58,250 --> 00:03:00,450 让我们继续 70 00:03:00,460 --> 00:03:05,120 然后10乘11就等于11后面加一个0 71 00:03:05,120 --> 00:03:06,960 也就说11-0 72 00:03:06,960 --> 00:03:13,070 最后,10乘12等于,120 73 00:03:13,080 --> 00:03:17,370 接下来,就是为了好玩,以上这些可以作为你的10的乘法口诀表 74 00:03:17,370 --> 00:03:20,460 但是现在你明白了其中的规律,你可以随意算这些乘法 75 00:03:20,470 --> 00:03:28,266 如果然我来问你,5732乘以10等于多少? 76 00:03:28,266 --> 00:03:29,691 结果会是多少呢? 77 00:03:29,691 --> 00:03:32,547 它就等于这个数字后面加一个0 78 00:03:32,547 --> 00:03:34,650 所以结果就是----我先不说出来 79 00:03:34,650 --> 00:03:39,080 5732后面加一个0 80 00:03:39,090 --> 00:03:40,122 还有就是让你知道一下 81 00:03:40,122 --> 00:03:42,445 我在这个数字后面写的这个小逗号 82 00:03:42,445 --> 00:03:45,882 这个就是为了能够读数字的时候更容易一点 83 00:03:45,882 --> 00:03:47,942 那么,你加一个逗号,你从个位数这边开始 84 00:03:47,942 --> 00:03:49,740 每三个数字你放一个逗号 85 00:03:49,750 --> 00:03:53,080 所以这个地方,我在这放一个逗号 86 00:03:53,080 --> 00:03:54,960 我就把这个逗号加在这个地方 87 00:03:54,960 --> 00:03:56,640 现在我很容易就能读出这个数 88 00:03:56,650 --> 00:03:59,690 这个逗号在这并没有加上或者取消任何数字 89 00:03:59,690 --> 00:04:01,190 它的作用就是帮我把这个数字变得更容易读 90 00:04:01,190 --> 00:04:07,890 现在这个5732乘以10就等于57,320 91 00:04:07,900 --> 00:04:09,195 我只需要在这加一个0 92 00:04:09,195 --> 00:04:12,708 但是那个是个很容易理解的乘法运算 93 00:04:12,708 --> 00:04:15,239 而且你注意到了吧,我们用5000乘以10 94 00:04:15,239 --> 00:04:19,070 所以当我们计算乘法时,我们得到了50000多的一个数字 95 00:04:19,070 --> 00:04:21,940 这个其实和5乘以10 等于50差不多的意思 96 00:04:21,950 --> 00:04:24,848 但是用的不是5,而是一个5000 97 00:04:24,848 --> 00:04:28,050 所以我得到了50,000什么什么和其他后面这些数字 98 00:04:28,060 --> 00:04:30,940 我们在以后的视频中会更多的学习如何计算这类问题 99 00:04:30,940 --> 00:04:32,512 但是,我觉得我得借此向你们介绍这个规律 100 00:04:32,512 --> 00:04:34,922 也就是这个在后面加一个0的小技巧 101 00:04:34,922 --> 00:04:37,690 你可以完全掌握这个10的乘法口诀表 102 00:04:37,690 --> 00:04:40,132 下面让我们来看11的乘法口诀表 103 00:04:40,132 --> 00:04:42,137 这些11的口诀表,开始的时候 104 00:04:42,152 --> 00:04:43,224 嗯,开始会比较容易 105 00:04:43,224 --> 00:04:47,140 但是随着数字越变越大,计算会越来越有点难 106 00:04:47,140 --> 00:04:49,000 好,11乘以0 107 00:04:49,000 --> 00:04:51,500 这个太容易,就等于0! 108 00:04:51,510 --> 00:04:52,820 11乘以1 109 00:04:52,830 --> 00:04:54,000 也很容易 110 00:04:54,000 --> 00:04:56,000 就等于11 111 00:04:56,010 --> 00:04:57,350 11乘以2? 112 00:04:57,360 --> 00:04:59,270 下面我们来看这个计算规律 113 00:04:59,270 --> 00:05:03,420 可以写成11+11,或者我们也可以算11次数字2的相加 114 00:05:03,430 --> 00:05:06,450 结果是22 115 00:05:06,450 --> 00:05:11,510 如果我们用11乘3,结果就等于33 116 00:05:11,510 --> 00:05:15,550 11乘4,等于4-4 117 00:05:15,560 --> 00:05:16,970 我觉得你开始认为这个很容易理解了吧 118 00:05:16,970 --> 00:05:18,980 11乘5等于多少呢? 119 00:05:18,990 --> 00:05:20,930 11x5等于55 120 00:05:20,930 --> 00:05:23,000 注意,我就把5写两遍 121 00:05:23,000 --> 00:05:24,930 那么11乘以6呢? 122 00:05:24,930 --> 00:05:27,320 等于66 123 00:05:27,330 --> 00:05:30,820 11乘以7呢? 等于84?哦,不对 124 00:05:30,830 --> 00:05:32,260 我在逗你呢 125 00:05:32,260 --> 00:05:33,710 我客不想把你搞糊涂 126 00:05:33,720 --> 00:05:34,255 但是,答案不是这个。不对 127 00:05:34,255 --> 00:05:36,910 没错,答案应该是77! 128 00:05:36,910 --> 00:05:37,902 7-7 129 00:05:37,902 --> 00:05:39,418 你就把这个数字写两遍 130 00:05:39,418 --> 00:05:41,086 7-7! 131 00:05:41,086 --> 00:05:42,630 让我换一个颜色来写 132 00:05:42,630 --> 00:05:46,250 11乘以8等于88 133 00:05:46,260 --> 00:05:50,420 11乘以9等于99 134 00:05:50,420 --> 00:05:52,405 行,那11乘12等于多少呢? 135 00:05:52,405 --> 00:05:54,495 11乘以12 136 00:05:54,495 --> 00:05:56,728 哦,不好意思,我错过了10。 137 00:05:56,750 --> 00:05:58,140 11乘以10 138 00:05:58,140 --> 00:06:00,150 你大概想说,应该是10再写一遍10 139 00:06:00,160 --> 00:06:00,720 错啦! 140 00:06:00,730 --> 00:06:01,410 那个完全错啦 141 00:06:01,410 --> 00:06:05,090 根本不是10-10 142 00:06:05,100 --> 00:06:06,844 那么,那个刚才我们用的小技巧 143 00:06:06,844 --> 00:06:08,433 就是两个数字重复写一遍的那个 144 00:06:08,433 --> 00:06:10,056 仅仅适用于一位数的数字 145 00:06:10,056 --> 00:06:11,602 也就是说,那个仅仅适用于从1到9的数字相乘 146 00:06:11,602 --> 00:06:12,825 11乘以10 147 00:06:12,825 --> 00:06:14,570 嗯,其实我们可以用几种方法来想这个问题 148 00:06:14,570 --> 00:06:16,740 我们可以在99后面加上11 149 00:06:16,750 --> 00:06:20,873 那么这变成了,99加11 150 00:06:20,888 --> 00:06:21,995 是什么呢? 151 00:06:21,995 --> 00:06:23,390 正好等于110 152 00:06:23,390 --> 00:06:24,809 我马上来给你展示一下怎么做这个 153 00:06:24,809 --> 00:06:28,879 哦,我希望你已经看过了怎么做两位数的加法的视频演示 154 00:06:28,879 --> 00:06:30,210 那这个结果就等于110 155 00:06:30,220 --> 00:06:34,153 或者你也可以从我们刚才学的的那个10的乘法口诀表的方法里方法 156 00:06:34,157 --> 00:06:36,652 在刚才,我们讲过11乘以10就等于11后面加一个0 157 00:06:36,652 --> 00:06:37,844 那么你得到了110 158 00:06:37,859 --> 00:06:39,590 那个位置是一个11 159 00:06:39,590 --> 00:06:42,541 最后,让我们来看11乘12 160 00:06:42,541 --> 00:06:44,694 11乘以12? 161 00:06:44,694 --> 00:06:46,007 实在是不容易记住这个口诀 162 00:06:46,007 --> 00:06:47,080 你只能想办法背一下这个规律 163 00:06:47,080 --> 00:06:48,180 或者你可以说,看吧 164 00:06:48,180 --> 00:06:51,310 这个就是11乘11再加11 165 00:06:51,310 --> 00:06:53,130 对不起,我老是跳过一些数 166 00:06:53,140 --> 00:06:55,410 让我们先来做11乘11 167 00:06:55,420 --> 00:06:56,700 咱们来确保这个地方能看清楚 168 00:06:56,700 --> 00:07:00,590 我们在做11乘12之前先来做11乘11 169 00:07:00,600 --> 00:07:05,480 那么11乘11就是11乘10再加11 170 00:07:05,490 --> 00:07:07,270 所以我们在这加上11 171 00:07:07,270 --> 00:07:13,120 11加上110等于121 172 00:07:13,120 --> 00:07:13,755 事实上,你看到了吧 173 00:07:13,755 --> 00:07:17,831 实际上这有一个11以上的数的乘法计算规则 174 00:07:17,846 --> 00:07:20,240 但是那个我还是放到以后的视频里面详细介绍 175 00:07:20,250 --> 00:07:23,715 好,最后,我们来看11乘12 176 00:07:23,715 --> 00:07:26,157 11乘以12 177 00:07:26,157 --> 00:07:28,552 我们可以用11相加12次 178 00:07:28,552 --> 00:07:30,760 也可以用12相加11次 179 00:07:30,760 --> 00:07:31,260 或者我们可以说 180 00:07:31,260 --> 00:07:37,910 嘿,这个就是11乘11再加11 181 00:07:37,910 --> 00:07:38,840 那么得多少呢? 182 00:07:38,850 --> 00:07:40,800 你可以把这个再加上11 183 00:07:40,810 --> 00:07:41,350 得到什么? 184 00:07:41,350 --> 00:07:45,975 你的结果是132 185 00:07:45,975 --> 00:07:49,551 我就说吧这个121再加上11 186 00:07:49,551 --> 00:07:50,998 就得到了132 187 00:07:50,998 --> 00:07:52,154 现在,另外还有一种方法就是,嗯 188 00:07:52,154 --> 00:07:54,028 10乘以12等于多少? 189 00:07:54,028 --> 00:07:54,987 10乘以12 190 00:07:54,987 --> 00:07:56,160 我们之前算过的 191 00:07:56,170 --> 00:07:58,570 那个结果是120 192 00:07:58,570 --> 00:08:00,888 那好,11乘以12 193 00:08:00,888 --> 00:08:03,038 因为我们是把12相加10次后再多加一次 194 00:08:03,038 --> 00:08:04,933 就是比那个再多12 195 00:08:04,933 --> 00:08:06,690 所以结果还是等于132 196 00:08:06,700 --> 00:08:10,090 那么有两种方法,都能得到同样的结果 197 00:08:10,100 --> 00:08:14,118 很好!现在我们来做12的乘法口诀表 198 00:08:14,118 --> 00:08:15,173 12的乘法口诀表 199 00:08:15,173 --> 00:08:16,378 你刚才已经知道了这些 200 00:08:16,378 --> 00:08:19,709 你已经准备好了来解决任何乘法运算的问题 201 00:08:19,709 --> 00:08:22,390 那个我们还是放到以后的视频再详细说 202 00:08:22,390 --> 00:08:23,983 还是,12乘0 203 00:08:23,983 --> 00:08:25,575 太容易啦,答案是0 204 00:08:25,575 --> 00:08:26,420 12乘1 205 00:08:26,430 --> 00:08:27,330 还是非常容易 206 00:08:27,330 --> 00:08:28,480 答案是12 207 00:08:28,490 --> 00:08:29,920 现在开始是有趣的部分了 208 00:08:29,930 --> 00:08:33,490 现在开始我们每次运算都增加12 209 00:08:33,505 --> 00:08:37,160 12乘2等于24 210 00:08:37,160 --> 00:08:40,041 12加12等于24,是吧? 211 00:08:40,041 --> 00:08:43,230 12 乘以--哦,这不是22 212 00:08:43,240 --> 00:08:44,160 我来重新写 213 00:08:44,160 --> 00:08:50,250 12乘3,那么就是12+12+12 214 00:08:50,250 --> 00:08:53,980 或者我们也可以把这儿写成12乘2 215 00:08:53,990 --> 00:08:56,070 我看我的脑子今天有点走神 216 00:08:56,070 --> 00:09:00,670 我们也可以把这个改写成12乘2再加12 217 00:09:00,670 --> 00:09:03,770 或者我们还可以写成24加12 218 00:09:03,770 --> 00:09:07,020 哪种都行,所有这些的结果都是等于36 219 00:09:07,030 --> 00:09:10,400 同时注意了,其实就是那里再加上12 220 00:09:10,400 --> 00:09:12,240 12乘4 221 00:09:12,250 --> 00:09:17,190 12乘4等于48 222 00:09:17,190 --> 00:09:18,270 有好多种方法你可以算出这个结果来 223 00:09:18,270 --> 00:09:21,155 你可以用11乘4得到44 224 00:09:21,155 --> 00:09:24,697 是不是?11乘4等于44 225 00:09:24,697 --> 00:09:30,029 然后你再加上一个4,就是你加了12次4 226 00:09:30,029 --> 00:09:32,851 或者你可以用12乘3等于36 227 00:09:32,851 --> 00:09:36,940 然后你再加一个12上去,就得到了48 228 00:09:36,950 --> 00:09:38,261 那种方法都可以 229 00:09:38,261 --> 00:09:40,300 这个是因为你可以用从任何一个方向进行相乘 230 00:09:40,300 --> 00:09:42,300 咱们继续说 231 00:09:42,300 --> 00:09:47,840 12乘5等于60 232 00:09:47,850 --> 00:09:51,694 10次5相加等于50,11次5相加就是55 233 00:09:51,694 --> 00:09:55,538 所以12次5相加就是60 234 00:09:55,538 --> 00:09:59,014 12乘6,等于多少啊? 235 00:09:59,014 --> 00:10:00,570 就是在这个基础上再加上12 236 00:10:00,580 --> 00:10:02,630 结果就等于72 237 00:10:02,630 --> 00:10:04,515 12乘以7? 238 00:10:04,515 --> 00:10:06,710 再来一个12 239 00:10:06,720 --> 00:10:09,747 72再加一个12,等于84 240 00:10:09,747 --> 00:10:13,157 知道嘛,我是认真的。事实上我比你们都大好多岁 241 00:10:13,157 --> 00:10:17,262 可是在我头脑里,我还是老得确认 242 00:10:17,262 --> 00:10:20,700 我得在12的乘法口诀表里面找到那些我背的分毫不差的部分, 243 00:10:20,700 --> 00:10:23,018 就好比,嗯,12乘5,然后有时候在我的脑袋里我想 244 00:10:23,018 --> 00:10:24,090 好吧,让我再来加上一个12 245 00:10:24,100 --> 00:10:26,290 对的,我记的完全正确 246 00:10:26,290 --> 00:10:28,480 12乘6等于72 247 00:10:28,490 --> 00:10:29,020 好的 248 00:10:29,020 --> 00:10:31,320 然后是12乘8 249 00:10:31,330 --> 00:10:33,685 在12乘7的结果上再加一个12 250 00:10:33,685 --> 00:10:35,400 等于96 251 00:10:35,400 --> 00:10:39,370 12乘9 252 00:10:39,370 --> 00:10:42,504 好,你在这个上面再加12。结果应该是108 253 00:10:42,504 --> 00:10:44,510 1-0-8 254 00:10:44,510 --> 00:10:46,700 然后是12乘10 255 00:10:46,700 --> 00:10:48,332 这个非常简单 256 00:10:48,332 --> 00:10:51,380 是吧?我们就在这个12后面加一个0。得到了120 257 00:10:51,380 --> 00:10:54,200 或者我们也可以在这个108上面加12 258 00:10:54,210 --> 00:10:55,570 那个方法都行 259 00:10:55,570 --> 00:10:58,290 12乘11 260 00:10:58,290 --> 00:10:59,406 这个我们做过了 261 00:10:59,406 --> 00:11:01,948 你在这个基础上再加12,得到了132 262 00:11:01,948 --> 00:11:05,077 最后来看12乘12 263 00:11:05,077 --> 00:11:08,931 这个等于144 264 00:11:08,931 --> 00:11:10,246 这个恰好向我们证明了 265 00:11:10,246 --> 00:11:13,777 如果我有一打的一打鸡蛋(一打是12个) 266 00:11:13,777 --> 00:11:17,010 或者比如说,我认为合计其实就是12个一打相加 267 00:11:17,010 --> 00:11:18,400 结果就是144个鸡蛋 268 00:11:18,410 --> 00:11:20,700 所以,其实在生活中,你将有很多机会见到这个数字 269 00:11:20,710 --> 00:11:22,550 比你想象的多很多次 270 00:11:22,550 --> 00:11:27,402 但是不管怎样,我们现在把所有的乘法口诀表都讲完了 271 00:11:27,410 --> 00:11:30,918 我真的特别希望你能够花些时间来把他们都背下来 272 00:11:30,920 --> 00:11:32,538 自己做点小提卡 273 00:11:32,538 --> 00:11:37,100 或者用我的网站上面的那个小软件工具 274 00:11:37,100 --> 00:11:38,850 你可以自己试试 275 00:11:38,860 --> 00:11:41,730 截止到2009年9月,他们都还正常的运行着 276 00:11:41,730 --> 00:11:45,044 我有很久一段时间没去碰它了,不过我正打算最近把他们再重新弄一下 277 00:11:45,044 --> 00:11:48,117 如果你在2009年正在看这个视频 278 00:11:48,117 --> 00:11:50,410 嗯,我可能不太会让它消失 279 00:11:50,420 --> 00:11:53,358 但是希望你们很快能用上一个更新更好版本的软件应用 280 00:11:53,360 --> 00:11:55,020 但是你必须得练习 281 00:11:55,020 --> 00:11:56,610 你应该让你的家长来考考你 282 00:11:56,620 --> 00:11:58,090 你应该自己弄点带备注的卡片 283 00:11:58,090 --> 00:12:00,853 你在上学的路上自己练习算算这些数-- 284 00:12:00,853 --> 00:12:02,180 12乘9等于多少? 285 00:12:02,190 --> 00:12:03,740 11乘11等于几? 286 00:12:03,750 --> 00:12:05,305 你得把每个题目自己做一遍 287 00:12:05,305 --> 00:12:08,690 因为在你未来的人生中你将会因此而受益匪浅 288 00:12:08,690 --> 00:12:10,630 下次视频见!