Hurry! By tomorrow morning, a reward of 10 points will be offered

Translation: The egrets are flying freely in front of Mount Cisai, the yellow-green fish on the river are swimming happily, and the peach blossoms floating in the water are so bright. An old man on the riverbank wore a blue hat and a green robe, braved the slanting wind and drizzle, and fished leisurely, he was fascinated by the beautiful spring scenery in the south of the Yangtze River, and he did not want to go home for a long time.

Appreciation This poem depicts the beautiful scenery of the water town in spring, creates the image of a fisherman, praises the life of the fisherman, and expresses the author's love for nature. The first sentence "the egret flies in front of the Xisai Mountain", "in front of the Xisai Mountain" points out the location, and the "egret" is a symbol of leisure, writing that the egret flies freely, setting off the leisurely self-satisfaction of the fisherman. The second sentence "peach blossom flowing water mandarin fish fat" means to say:

The peach blossoms are in full bloom, the river is soaring, and the mandarin fish are growing fat at this time. Here the peach and the water green contrast each other, which is to express the lake and mountains in front of the Xisai Mountain in late spring, rendering the living environment of the fisherman. Three or four sentences, "green hats, green clothes, slanting wind and drizzle do not need to return", describe the fisherman's attitude of fishing.

The fisherman wears a green hat and a green coat, and forgets to return in the slanting wind and drizzle. "Slanted wind" refers to a light breeze. The whole poem is brightly colored and the language is lively, vividly showing the leisurely life of the fisherman.

What do you want to ask, the thoughts and feelings of this poem?

In the beautiful scenery of the water town and the idealized life of a fisherman, this word embodies the author's love for freedom and nature. What attracts us more in the words is not the fisherman who is calm and comfortable in the wind and rain, but the picture of the spring river rising and misty rain during the peach blossom flood in Jiangxiang in February. The green mountains in the rain, the fishing boats on the river, the sky is blank, the red hearts on both sides of the bank, the color is bright but soft, and the atmosphere is quiet but full of vitality.

This not only reflects the author's artistic ingenuity, but also reflects his lofty, impulsive, and leisurely taste.

An old fisherman, sitting on a leisurely boat, fishing for fat mandarin fish, the old fisherman wears a coat made of brown and a hat made of hoops, and does not go home in the slanting wind and drizzle weather, because he is fascinated by the scenery of early spring.

1: Because sn=1 (n+1), s(n-1)=1 n, so an=sn-s(n-1)=1 (n+1)-1 n=-1 (n 2+n).

2: Because an-a(n-1)=3n

then a(n-1)-a(n-2)=3n-3

a(n-2)-a(n-3)=3n-6

a2-a1=6

The above equation is all added and subtracted, and an-a1=3*[n(n+1) 2-1]=3(n 2+n-2) 2

So an=3(n 2+n-2) 2-2=(3n 2+3n-10) 2

1, sn=1 (n+1), s(n-1)=1 n, and an=sn-s(n-1).

1/(n+1)-1/n

n-（n+1）]/n(n+1)

1 n(n+1) or is denoted as -1 (n2+n).

2，an-a(n-1)=3n, an=a(n-1)+3n

a(n-1)-a(n-2)=3（n-1） a(n-1)=a(n-2)+3（n-1）

a(n-2)-a(n-3)=3（n-2） a(n-2)=a(n-3)+3（n-2）

a(n-3)-a(n-4)=3（n-3） a(n-3)=a(n-4)+3（n-3）

a2-a1=a[n-(n-2)]-a[n-(n-1)]=6

a(n)=a（1）+3[n-(n-2)]+3（n-1）+3n

a（1）+3(2+..n) Entries n-1 in parentheses at the moment.

-2)+3*(n+2)(n-1)/2

3n^2+3n-10)/2

1 Solution: an=sn-sn-1=1 (n+1)-1 n2 solution: an-a(n-1)=3n

then a(n-1)-a(n-2)=3(n-1)a(n-2)-a(n-3)=3(n-1).

a3-a2=3*3=9

a2-a1=3*2=6

The equation adds to the left and the right to add, and has:

an-a1=3*(n+n-1+..3+2)=(3/2)(n+2)(n-1)

then an=(3 2)(n+2)(n-1)+a1=)=3 2)(n+2)(n-1)-2=3 2(n 2)+3 2n-5

i.e. an=3 2(n2)+3 2n-5

Carve. 2.Ten-day period.

3.Week. 4.Blink.

5.Through. 6.Former times.

7.Rising sun. 8.Daytime.

9.Evening. 10.Evening.

The software can search for the answer.

Finding the analytic formula of two functions can be found with a definite integral.

I've done this question ... It's from elementary school.