Question

tính nhanh

(\(\dfrac{1}{2}\) + 1).(\(\dfrac{1}{3}\) +1).(\(\dfrac{1}{4}\) +1)......(\(\dfrac{1}{999}\) +1)

Answer 1

=\(\dfrac{3}{2}\times\dfrac{4}{3}\times\dfrac{5}{4}\times...\times\dfrac{1000}{999}\)

=\(\dfrac{1000}{2}\)

=500

Chúc bạn học tốt nha.

Answer 2

\(\left(\frac{1}{2}+1\right).\left(\frac{1}{3}+1\right).\left(\frac{1}{4}+1\right).....\left(\frac{1}{999}+1\right)\\ < =>\frac{3}{2}.\frac{4}{3}.\frac{5}{4}....\frac{1000}{999}\\ < =>\frac{3.4.5....1000}{2.3.4....999}\\ =\frac{1000}{2}=500\)