Question

[ngocan le]

help me

\(\left(1-\frac{1}{2}\right).\left(1-\frac{1}{3}\right).\left(1-\frac{1}{4}\right).\left(1-\frac{1}{5}\right).......\left(1-\frac{1}{19}\right).\left(1-\frac{1}{20}\right)\)

ghi cách giải giùm mình nha cảm ơn nhìu :)))))

Answer 1

[Tạ Giang Thùy Loan]

Bạn tự viết lại đề bài nha

\(\frac{1}{2}\)x\(\frac{2}{3}\)x\(\frac{3}{4}\)x\(\frac{4}{5}\)x...x\(\frac{18}{19}\)x\(\frac{19}{20}\)

=\(\frac{1x2x3x4x...x18x19}{2x3x4x5x...x19x20}\)

=\(\frac{1}{20}\)

Answer 2

[My love Third Kamikaze]

= \(\frac{1}{2}\). \(\frac{2}{3}\).\(\frac{3}{4}\).\(\frac{4}{5}\). ... . \(\frac{18}{19}\).\(\frac{19}{20}\)

= \(\frac{1}{2}\)

tk cho mk nha, mik đg âm điểm huhu