Two calculation questions (a-b) ^ 6 (B-A), (a-b + C) (a + B + C)

（a-b)^6(b-a)
=-（a-b）^7
(a-b+c)(a+b+c)
=(a+c)^2-b^2
=a^2+2ac+c^2-b^2
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A. If B, C, D and e do one job, if a, B, C and D work together, it can be completed in 8 days; if B, C, D and e work together, it can be completed in 6 days; if a and e work together, it can be completed in 12 days, then a work alone______ It will be finished in three days

According to the meaning of the question, 1A + 1b + 1C + 1D = 18, 1b + 1C + 1D + 1E & nbsp; = 16, ② 1A + 1E & nbsp; = 112, ③ ① - ②, 1A − 1E = − 124, ④, ③ + ④, 2A = 124, a = 48. So a can finish the work in 48 days alone

The minimum factor of a non-zero natural number is (), the maximum factor is (), and the minimum multiple is ()

The minimum factor of a nonzero natural number is (1), the maximum factor is itself, and the minimum multiple is itself

A mathematical problem has a number that can be written as the sum of three continuous natural numbers, the sum of four continuous natural numbers, and the sum of five continuous natural numbers,

There are many such numbers, for example: 210 = 69 + 70 + 71; 210 = 51 + 52 + 53 + 54; 210 = 40 + 41 + 42 + 43 + 44; another example: 330 = 109 + 110 + 111; 330 = 81 + 82 + 83 + 84; 330 = 64 + 65 + 66 + 67 + 68. In general, if the number is m, then according to the meaning of the question, M = X-1 + X + X + 1 = 3x, then the number is a multiple of three, that is to say

Jingjing first writes out all integers from 1 to 10000 in order, and then erases those numbers that can't be divided by 5 or 11. Among the remaining numbers, what is the number in position 2008?

The number left can be divided by 5, 11 or 5 × 11 = 55! How many numbers are left before 55: 5, 10, 11, 15, 20, 22, 25, 30, 33, 35, 40, 44, 45, 50, 55, a total of 15

It is known that the least common multiple of three continuous natural numbers is 360. These three numbers are______ ．

360 = 2 × 2 × 2 × 3 × 3 × 5, 2 × 2 × 2 = 8, 3 × 3 = 9, 2 × 5 = 10; so these three numbers are 8, 9, 10

Some people say, "in any four natural numbers, the difference between at least two numbers is a multiple of three." is this sentence right? What do you think?

According to the stem analysis can be: for any four positive integers a, B, C, D divided by 3, there can be at most three different residues 0, 1, 2: (1) assuming that a, B, C residues are not the same, then the fourth number d divided by 3 can only be a residue of 0, 1, 2, so it is the same as a residue of a, B, C

There are 18 birds in the tree. Six birds fly away for the first time and seven birds fly away for the second time. How many less birds are left than before?

18-6 = 12, there are 12 after the first time
12-7 = 5. There are 5 more after the second time
18-5 = 13, 13 less than the original

A + A + a-b-b = 12 b + B + B-A-A = 2 how many are a and B respectively

Third grade? Well, I'll write it down to see if I can understand it
3A-2B=12
3B-2A=2
Multiply another equation by 2 to get 6a-4b = 24
Then multiply the two equations by 3 to get 9b-6a = 6
Add the two formulas 5B = 30. B = 6
If B = 6 is taken into two formulas, a = 8 can be obtained
Study hard!

1. Girls account for 80% of boys. There are four more boys than girls. How many boys?
2. Team a and team B built a highway. Team a built 60% of the total length of the highway, 60 meters more than team B. how many meters is the total length of the highway?

4 △ 0.2 = 20 persons
A: there are 20 boys
60 △ 0.2 = 300 m
A: the total length is 300 meters

Two calculation questions (a-b) ^ 6 (B-A), (a-b + C) (a + B + C)