\(A=\frac{2^2}{1.3}\cdot\frac{3^2}{2.4}....\frac{999^2}{998.1000}\)

\(A=\frac{2^2.3^2....999^2}{1.3.2.4.998.100}=\frac{\left(2.3.....999\right)\left(2.3....999\right)}{\left(1.2....998\right)\left(3.4....1000\right)}\)

\(A=999\cdot\frac{1}{500}=\frac{999}{500}\)( khúc này mk làm tắt, bn bỏ dấu ở trên rồi bỏ từng tử)

=?????????????????????????????????????????????????????????????????????????????????????????????????????????????????

ai choi freefire thi kb voi minh

Nhóm vào !                                                                                           

\(A=\frac{2^2.3^2.4^2............99^2}{1.3.2.4.3.5................998.1000}\)

\(A=\frac{1.2.3.4.5................999.1.2.3.4................999}{1.2.3.4.5.6.7..........1000.1.2.3.4..............998}\)

\(A=\frac{999.999}{1000.998}\)

\(Ko\)  \(\text{chắc lắm}\)

a, \(A=\frac{2^2}{1.3}.\frac{3^2}{2.4}.\frac{4^2}{3.5}...\frac{999^2}{998.1000}\)

\(=\frac{2.2}{1.3}.\frac{3.3}{2.4}.\frac{4.4}{3.5}...\frac{999.999}{998.1000}\)

\(=\frac{2.3.4...999}{1.2.3...998}.\frac{2.3.4...999}{3.4.5...1000}\)

\(=\frac{999}{1}.\frac{2}{1000}\)

\(=\frac{999.2}{1000.1}=\frac{999.2}{500.2.1}\)

\(=\frac{999}{500}\)

Vậy \(A=\frac{999}{500}\)

chúc bạn học giỏi

cảm ơn bạn nhiều nha

không có j đâu bạn

\(I=\frac{2^2}{1.3}.\frac{3^2}{2.4}.\frac{4^2}{3.5}...\frac{999^2}{998.1000}\)

\(I=\frac{2^2.3^2.4^2...999^2}{2.3^2.4^2...998^2.1000}\)

\(I=\frac{2}{1000}=\frac{1}{500}\)

\(=\frac{2\cdot2}{1\cdot3}\cdot\frac{3\cdot3}{2\cdot4}\cdot\frac{4\cdot4}{3\cdot5}\cdot...\cdot\frac{999\cdot999}{998\cdot1000}\)

\(=\frac{2\cdot2\cdot3\cdot3\cdot4\cdot4\cdot...\cdot999\cdot999}{1\cdot3\cdot2\cdot4\cdot3\cdot5\cdot...\cdot998\cdot1000}\)

\(=\frac{2\cdot3\cdot4\cdot...\cdot999}{1\cdot2\cdot3\cdot...\cdot998}\cdot\frac{2\cdot3\cdot4\cdot...\cdot999}{3\cdot4\cdot5\cdot...\cdot1000}\)

\(=\frac{999}{1}\cdot\frac{2}{1000}\)

\(=\frac{999}{500}\)

Adu

Skibidi 

=4/3.9/8.16/15.25/4096(CÁI NÀY MÌNH BIẾN NÓ VỀ PHÂN SỐ NHA)

=5/512 (BẠN THỰC HIỆN PHÉP TÍNH TỪ TRÁI SANG PHẢI NHÉ)

\(\frac{2^2}{1.3}.\frac{3^2}{2.4}.\frac{4^2}{3.5}.\frac{5^2}{4^6}=\frac{4}{3}.\frac{9}{8}.\frac{16}{15}.\frac{25}{4096}=\frac{4.9.16.25}{3.8.15.4096}=\frac{3.5}{2.3.256}=\frac{5}{2.256}=\frac{5}{512}\)

# Học tốt.!

=)))

\(\frac{2^2}{1.3}.\frac{3^2}{2.4}.\frac{4^2}{3.5}.....\frac{59^2}{58.60}\)

\(=\frac{2^2.3^2.4^2....59^2}{1.3.2.4.3.5....58.60}\)

\(=\frac{\left(2.3.4...59\right)\left(2.3.4...59\right)}{\left(2.3.4...58\right)\left(3.4.5....60\right)}\)

\(=\frac{59.2}{60}=\frac{59}{30}\)

\(A=\frac{2^2}{1.3}\cdot\frac{2^2}{2.4}\cdot\frac{2^2}{3.5}\cdot\frac{2^2}{4.6}\)

\(A=\frac{4}{3}\cdot\frac{1}{2}\cdot\frac{4}{15}\cdot\frac{1}{6}\)

\(A=\frac{4.1.4.1}{3.2.15.6}\)

\(A=\frac{4}{135}\)

\(\frac{2^2}{1.3}.\frac{3^2}{2.4}.\frac{4^2}{3.5}.\frac{5^2}{4.6}\)

\(=\frac{2.2}{1.3}.\frac{3.3}{2.4}.\frac{4.4}{3.5}.\frac{5.5}{4.6}\)

\(=\frac{2.3.4.5}{1.2.3.4}.\frac{2.3.4.5}{3.4.5.6}\)

\(=\frac{5}{1}.\frac{2}{6}\)

\(=\frac{5}{1}.\frac{1}{3}\)

\(=\frac{5}{3}\)

Đọc kỹ lại đề đi Trần Cao Vỹ Lượng