General term formula of sequence 1,3,6,10,15,51

General term formula of sequence 1,3,6,10,15,51

Is the sixth number wrong? It should be 21
Then the general expression should be n * (1 + n) 2

-18 ^ (- 2 cube of 3) + 5 × (- 3 / 2 cube) - (- 15) ^ 5

-18÷（-3²）+5×（-2³）-（-15）÷5
=-18÷(-9)+5×(-8)+3
=2-40+3
=-35
If you have any questions, please review the original question,

Given that the product of two primes is 143, what is the sum of the two primes?

11*13=143
11+13=24

What is the wisdom question 1 / (x-1) (X-2) + 1 / (X-2) (x-3) +. + 1 / (x-2004) (x-2005) equal to

1/(x-1)(x-2)+1/(x-2)(x-3)+.+1/(x-2004)(x-2005)
=1/(x-2)-1/(x-1)+1/(x-3)-1/(x-2)+.+1/(x-2005)-1/(x-2004)
=1/(x-2005)-1/(x-1)
=2004/[(x-2005)(x-1)]

Fill in 2,5,11,23, (), ()
1 / 2, 3 / 4, 5 / 8, 7 / 16, (), ()
1＋2,4＋2,9＋2,16＋2,（）,（）
4 8 2 16, 9 3 4 12, 8 7 4 14, 9 10 5
2,5,11,23，（），（）

1 / 2, 3 / 4, 5 / 8, 7 / 16, (9 / 32), (11 / 64) 1 + 2,4 + 2,9 + 2,16 + 2, (25 + 2), (36 + 2) 4 8 2 16, 9 3 4 12, 8 7 4 14, 9 10 5 (18)

Write 2006 as the sum of n (n > = 3) continuous natural numbers, please write two expressions (except 500 + 501 + 502 + 503 = 2006)
Please answer in detail

Please wait. 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18 + 19 + 20 + 21 + 22 + 23 + 24 + 25 + 26 + 27 + 28 + 29 + 30 + 31 + 32 + 33 + 34 + 35 + 36 + 37 + 38 + 39 + 40 + 41 + 42 + 43 + 44 + 45 + 46 + 47 + 48 + 49 + 50 + 51 + 52 + 53 + 54 + 55 + 56 + 57 + 58 + 59 + 60 + 61 + 62 + 63 = 2006110 + 111 +

A detailed introduction of friction formula

Note: friction is divided into sliding friction, rolling friction and static friction
(1) The formula of sliding friction in junior high school physics is as follows:
F = UFN (in the formula, f is sliding friction, FN is positive pressure, and u is sliding friction coefficient)
(2) If it is static friction, the calculation is decided according to the force analysis;
(3) If it is rolling friction, we don't need to do calculation and research in junior high school

Look at the law: 2, 3, 10, 15, 26, 35 What is the next number?

2,3,10,15,26,35,（50）
This problem is not easy to find the law at the beginning of Tao. You can try to use the law of square sum addition and subtraction to solve it, that is, 2 = 1 ^ 2 + 1, 3 = 2 ^ 2-1, 10 = 3 ^ 2 + 1, 15 = 4 ^ 2-1, 26 = 5 ^ 2 + 1, 35 = 6 ^ 2-1. According to this law, the number in () should be 7 ^ 2 + 1 = 50

The sum of three continuous natural numbers is 75. What is the product of these three continuous natural numbers?
Don't use equations,
Finally, it seems that the three numbers are 24, 25 and 26, but how did 24 and 26 come from,

75 △ 3 = 25 middle number
25－1＝24
25+1＝26
24×25×26＝15600
Do you understand what I'm doing,

(1) If 0 ＜ a ＜ B, prove: √ a ＜ B. (2). If a ＜ B, prove: the cubic root of a ＜ the cubic root of B

0 ＜ a ＜ B, proof: √ a ＜ B
It is proved that b > a > 0
So B-A > 0
(√b-√a)(√b+√a)＞0
And: √ B + √ a ＞ 0
That is: √ B - √ a ＞ 0
2) If a < B, prove that the root of a is less than the root of B
b-a=(b^1/3-a^1/3)(b^2/3+a^1/3b^1/3+b^2/3)＞0
b^2/3+a^1/3b^1/3+b^2/3＞0
So B ^ 1 / 3-A ^ 1 / 3 > 0
That is, the root of a is less than the root of B