S=1/5+1/6+1/7+1/8+1/9+1/10 so sánh S vs 3/5 12/11/2021 Bởi Aubrey S=1/5+1/6+1/7+1/8+1/9+1/10 so sánh S vs 3/5
Đáp án: Giải thích các bước giải: $S=\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}$ $ $ Ta có: $\dfrac{1}{5}>\dfrac{1}{10}$ ; $\dfrac{1}{6}>\dfrac{1}{10}$ ;…; $\dfrac{1}{10}=\dfrac{1}{10}$ $ $ $⇒\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}>\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}$ $ $ $⇒\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}>\dfrac{6}{10}$ $ $ $⇒\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}>\dfrac{3}{5}$ Bình luận
Đáp án:
Giải thích các bước giải:
$S=\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}$
$ $
Ta có: $\dfrac{1}{5}>\dfrac{1}{10}$ ; $\dfrac{1}{6}>\dfrac{1}{10}$ ;…; $\dfrac{1}{10}=\dfrac{1}{10}$
$ $
$⇒\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}>\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}+\dfrac{1}{10}$
$ $
$⇒\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}>\dfrac{6}{10}$
$ $
$⇒\dfrac{1}{5}+\dfrac{1}{6}+\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}>\dfrac{3}{5}$