Question

Giúp mik với : 1/99 - 1/99.98 - 1/98.97 - 1/97.96 - ...- 1/3.2 - 1/2.1

Answer 1

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\(= \frac{1}{99} - \left(\right. \frac{1}{99.98} + \frac{1}{98.97} + \frac{1}{97.96} + . . . + \frac{1}{3.2} + \frac{1}{2.1} \left.\right)\)

\(= \frac{1}{99} - \left(\right. \frac{1}{99} - \frac{1}{98} + \frac{1}{98} - \frac{1}{97} + \frac{1}{97} - \frac{1}{96} + . . . + \frac{1}{3} - \frac{1}{2} + \frac{1}{2} - \frac{1}{1} \left.\right)\)

\(= \frac{1}{99} - \left(\right. \frac{1}{99} - 1 \left.\right) = \frac{1}{99} - \frac{1}{99} + 1 = 1\)