Question

Bài 1: Tính nhanh: \(\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right)....\left(1-\frac{1}{50}\right)\)

Answer 1

=1/2 .2/3.3/4......49/50

=1/50

Answer 2

=1/2.2/3.3/4.4/5.........48/49.49/50

=1.2.3.4.....49/2.3.4.5...49.50

=1/50

thanks,chúc học tốt!

Answer 3

Ta có : 

\(\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)..................\left(1-\frac{1}{50}\right)\)

= \(\frac{1}{2}.\frac{2}{3}.\frac{3}{4}..........\frac{49}{50}=\frac{1.2.3..........49}{2.3.4.............50}=\frac{1}{50}\)

k nha bạn