Question

等比数列、第5题、拜托?

Answer 1

(5)

lgx+lg(x^2)+...+lg(x^10)=110

lg(x^55)=110

x^55 = 10^110

= 100^55

x=100

lgx+(lgx)^2+(lgx)^3+...+(lgx)^10

=2^1+2^2+2^3+...+2^10

= 2(2^10-1)