A= 1/4 ( 1/2x6 +1/6x10 +.............+1/46x50)
A= 1/4 ( 1/2 - 1/6 + 1/6 - 1/10 +.......... + 1/46 - 1/50 )
A= 1/4 ( 1/2 - 1/50 )
A= 1/4 x 12/25
A= 3/25
\(A=\frac{1}{2.6}+\frac{1}{6.10}+\frac{1}{10.14}+...+\frac{1}{46.50}\)
\(A=\frac{1}{8}\left(\frac{2}{1.3}+\frac{2}{3.5}+\frac{2}{5.7}+...+\frac{2}{23.25}\right)\)
\(A=\frac{1}{8}\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+...+\frac{1}{23}-\frac{1}{25}\right)\)
\(A=\frac{1}{8}\left(1-\frac{1}{25}\right)\)
\(A=\frac{1}{8}.\frac{24}{25}\)
\(A=\frac{3}{25}\)
sài rồi nhock phải làm theo anh mới đúng
A=1/2.6+1/6.10+1/10.14+.....+1/46.50
A=1/3(1/2-1/6+1/6-1/10+1/10-1/14+.....+1/46-1/50
A=1/3(1/2-1/50)
A=1/3.12/25
A=4/25
=12.6+16.10+110.14+...+146.50�=12.6+16.10+110.14+...+146.50
A=18(21.3+23.5+25.7+...+223.25)�=18(21.3+23.5+25.7+...+223.25)
A=18(1−13+13−15+15−17+...+123−125)�=18(1−13+13−15+15−17+...+123−125)
A=18(1−125)�=18(1−125)
A=18.2425�=18.2425
A=325
