A=\(\underset{2}{\overset{1}{\xrightarrow{}}}+\underset{6}{\overset{1}{\xrightarrow{}}}+\underset{18}{\overset{1}{\xrightarrow{}}}+............+\underset{4347}{\overset{1}{\xrightarrow{}}}=?\)

Ax3-A=\(\left(\underset{2}{\overset{1}{\xrightarrow{}}}+\underset{6}{\overset{1}{\xrightarrow{}}}+\frac{1}{18}+...........+\frac{1}{4347}\right)x3-\left(\frac12+\frac16+\frac{1}{18}+.............+\frac{1}{4347}\right)\)

Ax3-A=\(\frac12x3+\frac16x3+\frac{1}{18}\times3+.........+\frac{1}{4347}x3-\frac12-\frac16-\frac{1}{18}-.\ldots\ldots-\frac{1}{4347}\)

Ax2=\(\frac32+\frac12+\frac16+.......+\frac{1}{1449}-\frac12-\frac16-\frac{1}{18}-\ldots\ldots\ldots-\frac{1}{4347}\)

Ax2=\(\frac32-\frac{1}{4347}\)

Ax2=

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