Posted by Chris on Tuesday, December 22, 2009 at 4:26pm.
log10x + log10(x+1)=1
In other words
log base 10 + log base 10(x+1)=1
I need to show it algebraically not using calculator
Thanks a lot !

Advanced Math  Reiny, Tuesday, December 22, 2009 at 4:34pm
log10x + log10(x+1)=1
log10[x(x+1)] = 1
x(x+1) = 10^1
x^2 + x  10 = 0
x = (1 ± √41)/2
but for log10 x, x > 0
so x = (1 + √41)/2

Advanced Math  Chris, Tuesday, December 22, 2009 at 4:47pm
thanks for you help and especially explanation
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