Question

( 1 - 1/4 ) x ( 1 - 1/9 ) x ( 1 - 1/16 ) x ... x (1 - 1/100) x (1- 1/121) = ?

Answer 1

\(\left(1-\frac{1}{4}\right)\left(1-\frac{1}{9}\right)\left(1-\frac{1}{16}\right)...\left(1-\frac{1}{100}\right)\left(1-\frac{1}{121}\right)\)

=\(\frac{3}{4}.\frac{8}{9}.\frac{15}{16}....\frac{99}{100}.\frac{120}{121}\)

=\(\frac{1.3}{2.2}.\frac{2.4}{3.3}.\frac{3.5}{3.3}.....\frac{9.11}{10.10}.\frac{10.12}{11.11}\)

=\(\frac{\left(1.2.3.....9.10\right)\left(3.4.5.....11.12\right)}{\left(2.3.4.5.....10.11\right)\left(2.3.4.5....10.11\right)}\)

=\(\frac{12}{11.2}\)

=\(\frac{6}{11}\)

Answer 2

Cho em Hải 1100x1phần9 là bao nhiêu