A complete collection of composition topics describing winter Beautiful!

A complete collection of composition topics describing winter Beautiful!

Winter Sonata

Imagine writing 10 questions

The future of me (imagine myself in the future) the house in 20 years (imagine technology in 20 years) the future of Mother Earth (imagine the future of the earth) if I were XXX (imagine myself as someone, something, what would I do) if I had If you own something, what will you do? The meeting in 20 years

It is pointed out that the degree and term of the square of polynomial 2x, the square of y-4xy, the cubic power of X + the cubic power of 2Y are arranged according to the ascending power of X

Quartic binomial
The cubic power of 2Y - the square of 4xy + the square of 2x, the square of Y - the cubic power of X

To prove that the sum of inner angles of n-polygon is equal to (n-2) * 180 degrees

Known: n-sided A1A2... An
Verification: a1 + A2 +. + an = (n-2) * 180 degree
Proof: connect A1A2,..., a1an
(n-2) triangles, the sum of their inner angles is exactly the sum of the inner angles of the n-polygon
∴∠A1+∠A2.+...+∠An=（n-2)*180°

The first row of 4-order determinant is 2 1 / 3 4 - 3, the second row is 5 - 1 / 2 1 - 2, the third row is 3 1 / 4 2 - 5, and the fourth row is 4 10 - 5

C2 * 12
2 4 4 -3
5 -6 1 -2
3 3 2 -5
-4 12 0 5
r1-2r3,r3-2r2
-4 -2 0 7
5 -6 1 -2
-7 15 0 -1
-4 12 0 5
Expand by column 3, d = (- 1)*
-4 -2 7
-7 15 -1
-4 12 5
r1+7r2,r3+5r2
-53 103 0
-7 15 -1
-39 87 0
Expand by column 3, d = (- 1)*
-53 103
-39 87
c2+2c1
-53 -3
-39 9
r2+3r1
-53 -3
-198 0
= 198*3/12
= 99/2.

Simple calculation of score: 78x78 / 79 (78 / 79) 2008x200 / 2007 (200 / 207)

（78+1）×78/79-1 2008*200/2007
=79*78/79+78/79-1 =（2008-1）*200/2007
=2007*200/2007-200/2007
=77+78/79 =200-200/2007
=77 and 78 / 79 = 199 and 1807 / 2007

F (x) = [1-2e ^ (1 / x) / 1 + e ^ (1 / x)] * arctan1 / x, its left limit f (0-0) =?

Write the greatest common factor of the numerator and denominator in the following section: 18 / 24, 51 / 17, 24 / 36, 13 / 9, 91 / 49

6 7 17 4 1 1

-The square + 1 factorization of 36B

11×22＋22×33＋33×44＋44×55
Simple operation

11*11*2+11*11*2*3+11*11*3*4+11*11*4*5
=11*11*(2+6+12+20)
==121*40
=4840