Question

THỰC HIỆN PHÉP TÍNH SAU:

a/\(\dfrac{1}{1.2}\)+\(\dfrac{1}{2.3}\)+\(\dfrac{1}{3.4}\)+...........+\(\dfrac{1}{99.100}\)

b/\(\dfrac{5.4^{15}-9^9-4.3^{10}.8^9}{5.29-6^{19}.7.2^{29}.27^6}\)

Answer 1

a) \(\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+....+\dfrac{1}{99.100}\)

= \(\dfrac{1}{1}-\dfrac{1}{2}+\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{4}+....+\dfrac{1}{99}-\dfrac{1}{100}\)

=\(\dfrac{1}{1}+0+0+...+0-\dfrac{1}{100}\)

=\(1-\dfrac{1}{100}\)

= \(\dfrac{99}{100}\)

Answer 2

a)

=

=

=

=