ta thay :\(\dfrac{1}{2}\)>\(\dfrac{1}{2^{100}}\)
\(\dfrac{1}{3}\)>\(\dfrac{1}{2^{100}}\)
............................
\(\dfrac{1}{2^{99}}\)>\(\dfrac{1}{2^{100}}\)
cộng vế theo vế ta dc:1+\(\dfrac{1}{2}\)+....+\(\dfrac{1}{2^{100}}\)>\(\dfrac{1}{2^{100}}\)+.....+\(\dfrac{1}{2^{100}}\)<50
đến đây bạn tự làm nhé