Ta có: \(1-\frac{1}{2}.\frac{2}{3}....\frac{98}{99}\)
= \(1-\frac{1}{99}\)
= \(\frac{98}{99}\)
P=\(1-\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right).........\left(1-\frac{1}{99}\right)\)
P=\(\frac{1}{2}.\frac{2}{3}.\frac{3}{4}.........\frac{98}{99}=\frac{1}{99}\)
\(P=1-\frac{1}{2}.\frac{2}{3}.\frac{3}{4}.....\frac{98}{99}=1-\frac{1}{99}=\frac{98}{99}\)
Nha ban Speed Ninja
P=1-\(\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)...\left(1-\frac{1}{99}\right)\)
P=\(1-\frac{1}{2}.\frac{2}{3}...\frac{98}{99}\)
P=1-1/99=98/99
P= 1-1/2x2/3x...x98/99
P= 1/2x2/3x...x98/99
P= 1/99
\(P=1-\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)....\left(1-\frac{1}{99}\right)=1-\frac{1}{2}.\frac{2}{3}....\frac{98}{99}=1-\frac{1}{99}=\frac{98}{99}\)