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Observe the number of the following columns in order of + 2, - 4, + 6, - 8, + 10. According to its sorting rule, the number of 2012 should be?
-4024
-1 / 2 2 / 3 - 3 / 4 4 / 5 - 5 / 6 6 / 7 If this column number is infinite, which two numbers are getting closer and closer
1 and - 1
What is the 2009 number 1, - 1 / 2,1 / 3, - 1 / 4,1 / 5, - 1 / 6? If a column of numbers is infinitely arranged, it will be closer to that number?
1 / 2009 is getting closer to 0
-What is the 2010 number? If this column of numbers is infinite, what is the number -1,1 / 2, - 1 / 3,1 / 4, - 1 / 5,1 / 6, - 1 / 7. What is the number 2010? If this column of numbers goes down infinitely, it will be closer and closer to the number
1 in 2010 is close to 0
Explore the law: like - 1, 2 minutes straight, 1 / 3. What number is 2008? If this column number is infinitely arranged, which number is closer and closer Within 5 points
The number 2008 is one in 2008 (1 / 2008)
At the end of the day, the number is getting closer to zero - that is, the sequence tends to zero
-1 / 2,1 / 3, - 1 / 4,1 / 5, - 1 / 6 if this column of numbers goes down infinitely, which number is closer to
Zero
If you divide the odd and even digits, they are getting closer to zero
0-9 (10 numbers) three numbers arranged in a group, how many groups can be arranged, the formula =?
A（10,3）＝720
The combination number of 3 out of 10 is t = 10 * 9 * 8 / 3 * 2 * 1 = 120. Why? Is there a formula? What formula?
yes.
Since the number of elements in the subset is 1 024 * 3, the number of elements in the subset is 1.024 * 8
How many permutations and combinations can there be in a group of four numbers from 0 to 9? Who knows the formula
210 combinations
10C4=210
The formula is: NCR
nCr= n!/r!(n-r)!
What kind of algorithm should be used for the four numbers 5, 5, 5, 1 to make the equation equal to 24?
(5-1/5)X5=24
RELATED INFORMATIONS
- 1. How do these numbers find the rule 1, 2, 4, 8, 16, 32 Up to 64, how much does it add up to? What is the rule formula?
- 2. When to use combination formula and when to use permutation formula? Don't give me from Baidu Encyclopedia to get that entry to me, I want to tell me specifically, an example, I understand
- 3. How many five digits can you make up with 12345?
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- 7. Look at the following list: half, one sixth, one twelfth, one twentieth Please find out the rule of arrangement and press here Fill in the blank regularly The fifth number is—— The number in 2011 is——
- 8. -3 / 4, 5 / 7, - 10 / 9, 17 / 13, - 33 / 16 to find the law, what is the number 2012
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- 13. Chinese mathematicians Who knows? Easy!
- 14. The definition of Pythagorean theorem, specific
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