Observe the following three lines: - 3, 9, - 27, 81, - 243 -5，7，-29，79，-245，… -1，3，-9，27，-81… (1) What is the order of the first row? (2) What is the relationship between the number of the second and third rows and the number of the first row? (3) Take the 10th number of the three rows and calculate the sum of the three numbers

Observe the following three lines: - 3, 9, - 27, 81, - 243 -5，7，-29，79，-245，… -1，3，-9，27，-81… (1) What is the order of the first row? (2) What is the relationship between the number of the second and third rows and the number of the first row? (3) Take the 10th number of the three rows and calculate the sum of the three numbers

（1）-3=（-1）131，9=（-1）232，-27=（-1）333，81=（-1）434，… So the n-th term is (- 1) n3n; (2) the number of the second row and each corresponding number of the first row plus - 2, the n-th term is (- 1) n3n-2; the number of the third row and each corresponding number of the first row multiplied by 13, the n-th term is (- 1) n3n-1; (3) the 10th number of the first row is (- 1) 10310 = 310; the 10th number of the second row is (- 1) 10310-2 = 310-2; the 10th number of the first row is (- 1) 10310-2 = 310-2 The sum of these three numbers is 310 + 310-2 + 39 = 7 × 39-2

Look at the following three lines, - 3,9, - 27,81, - 243 1,13,-23,85,-239…… 1,-3,9,-27,81
First line: - 3,9, - 27,81, - 243
The second line: 1,13, - 23,85, - 239
The third line: 1, - 3, 9, - 27, 81
1. What is the relationship between the number of the second and third rows and the number of the first row?
2. What is the difference between the sum of the sixth number in the second and third rows and the sixth number in the first row?

The first line; - 3 to the nth power
Second line; - 3 to the nth power + 4
The third line; - 3 n minus one power
Each number in the second row is 4 more than that in the first row
; - 6 minus 1 power of 3 - (- 6 power of 3 + 4) = - 976

Observe the following numbers: (1) - 3,9, - 27,81, - 243729. (2) 0,12, - 24,84, - 243729. (3) - 1,3, - 9,27, - 81243
(1) What is the order of the number of the first row? (2) is there any relationship between the number of the second and third rows and the number of the first row?

(1) Each term is multiplied by (- 3) to get the next term
(2) The second line has nothing to do with the number of the first line. The law of the third line is the same as that of the first line

The following three groups were observed: ① - 3,9, - 27,81, - 243729 ··· ② 0,12, - 24,84, - 240732···
③-1,3,-9,27,-81,243···
Take the 10th number of each row and calculate the sum of the three numbers

The general formula is
1. The nth power of (- 3)
2.12 * (n-1) times (- 1) to the nth power
3. The N-1 power of 3 is multiplied by the n-th power of (- 1)
When n = 10
The sum is 78840