Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1+2+3+4+5+...+99+100( có 100 số hạng)
=(1+100).100÷2
=101.50
=5050
Gau Xơ đã làm bài toán này như sau :
Gau Xơ nhận thấy rằng cặp 2 số đầu và cuối , cũng như từng cặp 2 số cách đều số đầu và số cuối đều có tổng bằng 101.
Có 50 cặp như thế, do đó kết quả là : 101.50 = 5050
Nếu tôi giả bài toán này thì theo tôi là có 3 cách làm ( kể cả cách Gau Xơ làm thế )
Ta có : 5A = 5 + 5^2 +...+ 5^51
=> 5A - A = 4A = 5^51 - 1
=> A = \(\frac{5^{51}-1}{4}\)
\(C=\frac{1}{3}+\frac{1}{3^2}+\frac{1}{3^3}+...+\frac{1}{3^{99}}\)
\(\Leftrightarrow3C=1+\frac{1}{3}+\frac{1}{3^2}+...+\frac{1}{3^{98}}\)
\(\Leftrightarrow3C-C=1-\frac{1}{3^{99}}\)
\(\Leftrightarrow2C=1-\frac{1}{3^{99}}\)
\(\Leftrightarrow C=\frac{1-\frac{1}{3^{99}}}{2}=\frac{1}{2}-\frac{1}{2-3^{99}}\)
Vậy \(C< \frac{1}{2}\)\(\left(DPCM\right)\)
Hi, my name is Vy and I'm 11 years old. I am currently in Nghi Kim High School, 6th grade. My school is quite large, consisting of three main houses. There is a lawn, library. My school is very modern. The students here are very friendly, the teachers are very enthusias. I am very happy to be there.
Hi, my name is Vy and I'm 11 years old. I am currently in Nghi Kim High School, 6th grade. My school is quite large, consisting of three main houses. There is a lawn, library. My school is very modern. The students here are very friendly, the teachers are very enthusias. I am very happy to be there.
Hi, I'm Thao. I'm 10 years old and I'm from grade 5C. Hung Binh Primary School is on Nguyen Xuan On street. My favorite is Music. I playing guitar and piano and poking out. I also listening to Korean and ang music. My family has 4 people, my father, my mother, my daughter and I. My father is 43 years old, working as a construction manager. My mother is 38 years old and currently I was still a 7-year-old student who also attended Hung Binh Primary School
Hi, I'm Thao. I'm 10 years old and I'm from grade 5C. Hung Binh Primary School is on Nguyen Xuan On street. My favorite is Music. I playing guitar and piano and poking out. I also listening to Korean and ang music. My family has 4 people, my father, my mother, my daughter and I. My father is 43 years old, working as a construction manager. My mother is 38 years old and currently I was still a 7-year-old student who also attended Hung Binh Primary School
Học tốt !
Đơn xin theo học lớp nhạc họa
- Trình bày liền mạch các đề mục trong đơn, thừa thông tin.
- Sửa thành:
Ngày/ tháng/ năm
Quê quán: Vĩnh Bảo- Hải Phòng
Chỗ ở hiện nay: phường Hồng Bàng, thành phố Hải Phòng.
