solve for x and show steps: log(x-2)-logx=3
we solved for x in the other question; its 8 .... right?
log is 10 base here right?
yeah log base 10
\[10^{(log(x-2)-log(x))}=10^3\] \[\frac{10^{log(x-2)}}{10^{log(x)}}=10^3\] \[\frac{x-2}{x}=1000\]
\[\frac{x-2}{x}=1000\] \[\frac{x}{x}-\frac{2}{x}=1000\] \[1-\frac{2}{x}=1000\] \[-\frac{2}{x}=999\] i think its right, but that looks peculiar
thats what i got but i wasnt sure. i did it a different way too
its about -.104791 if it is
different ways are good, i tend to try to show that math aint got to be done in one specific move
when you plug x back in, does it make the equation equal?
cant tell yet :) i havent tried to compute it
log(x-2)/x =3 10^log(x-2)/x =10^3 (x-2)/x = 1000 x-2 = 1000x -2 = 999x x = -2/999
ugh, cant have x = a negative number for starters
true i forgot about that
but wolfram gives the answer as a negative too , so i dunno
would it be no solution?
http://www.wolframalpha.com/input/?i=log%28x-2%29-log%28x%29+%3D+3&a=*FunClash.log-_*Log10.Log- no were right, somehow; but wolf was reading it as ln, had to tell it to do log
okay so is the answer x=-2/999 or no solution?
im going with -2/999
alright thanks
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