Question

B1 : Tính nhanh

A= (1+\(\dfrac{2}{4}\)).(1+\(\dfrac{2}{10}\)).(1+\(\dfrac{2}{18}\))...(1+\(\dfrac{2}{10098}\))

B2 : Cho\(\dfrac{1}{a}\)+\(\dfrac{1}{b}\)+\(\dfrac{1}{c}\)= 0

Tính \(\dfrac{bc}{a^2}\)+ \(\dfrac{ca}{b^2}\)+\(\dfrac{ab}{c^2}\)

B3 : Cho\(\dfrac{x}{x^{2^{ }}-x+1}\)=\(\dfrac{1}{3}\)

Tính S=\(\dfrac{x^2}{x^4+x^2+1}\)

Answer 1

Ribi Nkok Ngok lê thị hương giang Nguyễn Huy Tú Nguyễn Nam Vũ Elsa