Chứng minh:\(\dfrac{1}{3}\)-\(\dfrac{2}{3^2}\)+\(\dfrac{3}{3^3}\)-\(\dfrac{4}{3^4}\)+...+\(\dfrac{99}{3^{99}}\)-\(\dfrac{100}{3^{100}}\)<\(\dfrac{3}{16}\)

Tìm các số nguyên tố x,y sao cho:x² +45=y²