Question

[Nguyễn Thùy Chi]

Tính

A= 7/3×4+9/4×5+11/5×6+13/6×7×15/7×8+17/8×9

Lm nhanh giúp mk nha. Mk đang cần gấp. Mk tick cho

Answer 1

[Nguyễn Lê Phước Thịnh]

\(A=\dfrac{1}{3}+\dfrac{1}{4}+\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{8}+\dfrac{1}{9}\)

=1/3+1/2+2/5+1/3+2/7+1/4+1/9

=2789/1260