# Math Help - Corrected the error : 1,2,3

1. ## Corrected the error : 1,2,3

Corrected the error and explanation of

1 )
2)
3 ) x real number :

2. 1) $ln (\frac{x+1}{x-2})=ln |x+1|-ln |x-2|$

2) $\sqrt{(1-\sqrt2)^2}=\sqrt{2}-1$

3) $\frac{1}{x}>2 \implies 1>2x$ AND $1>2x \implies \frac{1}{x}>2$ if and only if $x>0$.

3. For the first and second question Thank you .
for 3 ) : this expression in the single resolution :

4. Originally Posted by dhiab
For the first and second question Thank you .
for 3 ) : this expression in the single resolution :
Fair enough. Sorry.