a) \(=\frac{3}{2}.\frac{4}{3}....\frac{100}{99}=\frac{100}{2}=50\)
a) =3/2 . 4/3 . 5/4 ...100/99
=\(\frac{3.4.5...100}{2.3.4..99}\)
=\(\frac{100}{2}\)
b) =
b) = \(\frac{-1}{2}.\frac{-2}{3}.\frac{-3}{4}...\frac{-99}{100}=-1\left(\frac{1.2.3...99}{2.3.4...100}\right)=-\frac{1}{100}\)
mk trả lời thiếu b,
b) =\(-\frac{1}{2}.-\frac{2}{3}.-\frac{3}{4}...-\frac{99}{100}\)
= -1.-2.-3...-99 / 2.3.4....100
= -1/100
phần a bạn rút gọn đi nha!
a, \(\left(\frac{1}{2}+1\right).\left(\frac{1}{3}+1\right).\left(\frac{1}{4}+1\right)...\left(\frac{1}{99}+1\right)\)
\(=\)\(\frac{3}{2}.\frac{4}{3}.\frac{5}{4}...\frac{100}{99}\)
\(=\frac{3.4.5...100}{2.3.4...99}\)
\(=\frac{100}{2}=50\)
b, \(\left(\frac{1}{2}-1\right).\left(\frac{1}{3}-1\right).\left(\frac{1}{4}-1\right)...\left(\frac{1}{100}-1\right)\)
\(=\frac{-1}{2}.\frac{-2}{3}.\frac{-3}{4}...\frac{-99}{100}\)
\(=\frac{1}{-2}.\frac{-2}{3}.\frac{3}{-4}...\frac{-99}{100}\)
\(=\frac{1}{100}\)
a, \(=\frac{3}{2}.\frac{4}{3}.\frac{5}{4}...\frac{100}{99}\)
\(=\frac{3.4.5...100}{2.3.4...99}\)
\(=\frac{100}{2}=50\)
b,\(=\frac{-1}{2}.\frac{-2}{3}.\frac{-3}{4}...\frac{-99}{100}\)
\(=-\frac{1.2.3...99}{2.3.4...100}\)
\(=-\frac{1}{100}\)
