Question

[Lê Thị Bích Thảo]

1/3+1/9+1/27+1/81+1/243+1/729 =?

Answer 1

[Harry Potter]

\(\frac{1}{3}\)+ \(\frac{1}{9}\)+ \(\frac{1}{27}\)+ \(\frac{1}{81}\)+ \(\frac{1}{243}\)+ \(\frac{1}{729}\)

= \(\frac{243}{729}\)+ \(\frac{81}{729}\)+ \(\frac{27}{729}\)+ \(\frac{9}{729}\)+ \(\frac{3}{729}\)+ \(\frac{1}{729}\)

= \(\frac{\left(243+27\right)+\left(81+9\right)+\left(3+1\right)}{729}\)

= \(\frac{270+90+4}{729}\)

=\(\frac{364}{729}\)

:)

Answer 2

[Lê Thị Bích Thảo]

Tính nhanh mà