lim x đến 0 ( 1+x)(1+2x)(1+3x)...(1+2019x)-1/x bằng
Giải thích
Lời giải
Chọn C
Ta có limx→01+x1+2x1+3x...1+2019x−1x
=limx→0x1+2x1+3x...1+2019xx+limx→011+2x1+3x...1+2019x−1x
=1+limx→01+2x1+3x...1+2019x−1x
=1+limx→02x1+3x...1+2019xx+limx→01+3x...1+2019x−1x
=1+2+limx→01+3x...1+2019x−1x=....=1+2+...+2019=20191+20192=1010.2019.