1.2x＊（1+（x-1000）/2000）^1.6=6772

150.8

91=（7　）＊（13 ）
14=（ 3）+（11　）＝（　17）－（ 3）
24=（13）+（11 )=( 27 )-( 3 )
70=( 7）*（2 )*(5 ) 填质数
我们是连续的自然数,质数说（ 2,3,5,7 ） 我们的和是11,和数说 ）
我是最小的合数（4 ） 我既是质数,又是偶数（ 2 ）

490×99×489÷490
＝490÷490×99×489
＝1×99×489
＝（100－1）×489
＝100×489－1×489
＝48900－489
＝48411

等于49452832.

780÷（80）=（9）.60
780÷（90）=（8）.60
780÷（120）=（6）.60
780÷（144）=（5）.60
780÷（180）=（4）.60
780÷（240）=（3）.60
780÷（360）=（2）.60
780÷（720）=（1）.60

【1-(1/4+3/8)】除以1/4=【1-(2/8+3/8)】/1/4=(1-5/8)/1/4=(3/8)/1/4=(3/8)*4=3/2

（0.04)^2005＊{（-5）^2005}^2
=[(0.2)^2]^2005*{（-5）^2005}^2
={[0.2*(-5)]^2}^2005
=[(-1)^2]^2005
=1

x=1899.854

1/19*21+1/21*23+----+1/97*99
=1/2*(1/19-1/21+1/21-1/23+1/23-1/25+-----+1/97-1/99)
=1/2*(1/19-1/99)
=40/1881

我只记得一个公式

〖1〗+〖7〗=〖8〗,〖9〗-〖6〗〖3〗,〖4〗x〖5〗=〖20〗

1125

10050

live very happily today! In the morning, it is very fine! Then I climb the mountain with family, the air on the mountain is very fresh, the flowers plants and trees on the mountain all seem extremely beautiful. In the afternoon, I go to friend's home to play, the friend entertains me warmly, show me a lot of books of his , has listened to his CD for me , then also ask me to eat a sumptuous dinner. Coming back home in the evening, family and I sat and watched TV together, we are returning and eating the fruit while chatting, the whole family is happy and harmonious!
译文：今天我过得非常开心!早上,天气非常好!于是我和家人一起去登山,山上的空气非常清新,山上的花草树木都显得格外美丽.下午,我去了朋友家玩,朋友热情地招待我,给我看了他的很多书,给我听了他的CD,然后还请我吃了一顿丰盛的晚餐.晚上回到家,我与家人坐在一起看电视,我们还一边聊天一边吃着水果,全家其乐融!
January 18 2005
I have rested for a week. I began to feel bored. So I went out with my friends. They are my best friends in the middle school. We didn’t go to someplace special. We just saw the other. We had lunch together. While we were having lunch, we were still talking about the new school and new friends. Yes! A year later, we have grown riper. And we learned much more things and got new life. We haven’t enough time to play, to waste and to lose the way. We only have two years. Two years to go, we will get the real life which belongs to us.
January 18 2005 年
我休息了一个星期.我开始了对感觉乏味.如此我出去了与我的朋友.他们是我的最好的朋友在中学.我们没去在某处特别.我们看见了其他.我们一起吃了午餐.当我们吃午餐, 我们仍然谈论新学校和新朋友.是! 一年后, 我们增长更加成熟.并且我们学会了更多事和有新生活.我们没有足够时间演奏, 浪费和迷路.我们只有二年.二年去, 我们将有属于我们的真正的生活.

x+6x+5x+25=505
12x+25=505
12x=480
x=40
累

14

X（1－5／8）＋（84－X）＊1／4＝26
3X/8+21-X/4=26
3X/8-X/4=26-21
X/8=5
X=5*8
X=40

应该是等于0,化解之后,关键是-x的四次方应该转换成x的四次方,之后他们的指数都变成了3n+4,而底数符号相反,抵消.

x/(x-1)+4/(x+1)=2/(x＊x-1) 左边通分得到 x(x+1)/(x-1)(x+1)+4(x-1)/(x-11)(x+1)=2/(x-1)(x+1) 约去分母 x(x+1)+4(x-1)=2 x^2+5x-6=0 (x-1)(x+6)=0 x=1 和x=-6 当x=1时,x＊x-1=0,分母为0,方程没有意义,所以,方程只有一个解即x=-6