Question

mi ajudem urgente

racionalize 2 sobre ✓2 +1

Answer 1

Multiplico pelo conjugado ... 

$\frac{2}{ \sqrt{2} +1} \\\\\\ \frac{2}{ \sqrt{2}+1 } \ .\ \frac{ \sqrt{2} -1}{ \sqrt{2} -1} \\\\\\ \frac{2.( \sqrt{2} -1)}{( \sqrt{2} +1) .( \sqrt{2} -1) } \\\\\\ \frac{2 \sqrt{2} -2}{( \sqrt{2})^{2} -(1)^{2}} \\\\\\ \frac{2 \sqrt{2} -2}{2-1} \\\\\\ \frac{2 \sqrt{2} -2}{1} =\boxed{\boxed{2 \sqrt{2} \ -2}}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ok$

Answer 2

    2     =      2(✓2 -1 )       =  2(✓2 -1)  ==> 2(✓2 -1) ==> 2(✓2 -1)
✓2 +1      (✓2 +1)(✓2 -1)      V2² - 1²               2 - 1                 1