\(\left(1+\frac{1}{100}\right).\left(1+\frac{1}{99}\right)............\left(1+\frac{1}{2}\right)\)

\(=\frac{101}{100}.\frac{100}{99}..............\frac{3}{2}\)

\(=\frac{101.100............3}{100.99...............2}\)

\(=\frac{101}{2}\)

2 x 15 = 30

​3 x 10 = 30

Chúc bạn học tốt^-^

2 x 15 = 30

3 x 10 = 30

Ta có: \(\left(x-y\right)^2\ge0\forall x;y\)\(\Rightarrow2xy\le x^2+y^2\Rightarrow4xy\le x^2+y^2+2xy=\left(x+y\right)^2=4\)

\(\Rightarrow xy\le1\)đpcm

Dấu "=" khi x = y = 1.

x : 2 = 4

x = 4 x 2 

x =    8