Question

tim x biet:

( 1/2 +1/3+ 1/4+ 1/5+ 1/6 +1/7)x (2009 * x ) = 0.63* 0.12 - 2,1 * 0,036

Answer 1

* là gì vâyk

Answer 2

bn viết lại đề đc k ? Tớ k hiểu j cả

Answer 3

bài này x=0

Answer 4

(1/2+1/3+1/5+1/5+1/6+1/7)x(2009.x)=0,63*0,12-2,1*0,036

(1/2+1/3+1/4+1/5+1/6+1/7)(2009*x)= \(\frac{21.3.12}{100.100}-\frac{21.12x3}{10.1000}\)

(1/2+1/3+1/4+1/5+1/6+1/7)(2009*x)=0

=> 2009.x=0( vì \(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{5}+\frac{1}{6}+\frac{1}{7}\ne0\)

=> x=0