tim gia tri nho nhat

A=/x+1/+/x+2/+/x+3/

B=/x-2017/+/x-2018/+/x-2019/

CM \(\dfrac{a}{b}+\dfrac{b}{a}>hoac=2\)

R=\(\dfrac{1}{2.32}+\dfrac{1}{3.33}+...+\dfrac{1}{1976+2006}\)

S=\(\dfrac{1}{2.1977}+\dfrac{1}{3.1978}+...+\dfrac{1}{31.2006}\)

tinh \(\dfrac{R}{S}\)

1 CM

a, \(\left(\dfrac{1}{1}+\dfrac{1}{3}+\dfrac{1}{5}+...+\dfrac{1}{2n-1}\right)-\left(\dfrac{1}{2}+\dfrac{1}{4}+...+\dfrac{1}{2n}\right)=\dfrac{1}{n+1}+\dfrac{1}{n+2}+...+\dfrac{1}{2n}\)( n∈Z)

b, \(\dfrac{1}{26}+\dfrac{1}{27}+...+\dfrac{1}{50}=\dfrac{99}{50}-\dfrac{97}{49}+...+\dfrac{7}{4}-\dfrac{5}{3}+\dfrac{3}{2}\)

M=\(\dfrac{42-x}{x-5}\). tim x∈Z de m nho nhat

cho \(\dfrac{x}{y}=\dfrac{2}{3}\).tinh M = \(\dfrac{5x+3y}{6x-7y}\)

cho x/y=2/3. tinh m = 5x+3y/6x-7y

tim so nguyen x, y\(\dfrac{x}{2}-\dfrac{2}{y}=\dfrac{1}{2}\)

ko tinh

a,\(2020-\dfrac{1}{3^2}-\dfrac{1}{4^2}-...-\dfrac{1}{2019^2}\)

b,\(\dfrac{1}{5}+\dfrac{1}{6}+...+\dfrac{1}{17}\)

CM\(\dfrac{1}{5}< \dfrac{1}{4^2}+\dfrac{1}{5^2}+...+\dfrac{1}{100^2}< \dfrac{1}{3}\)