Помогите плиз решить номер 41 и 42

41)

$\dispaystyle \frac{100^5}{(80+20)^{10}}*50^5= \frac{100^5}{100^{10}}*50^5= \frac{1}{100^5}*50^5= \frac{50^5}{(2*50)^5}= \frac{1}{2^5}= \frac{1}{32}$

42)

$\dispaystyle \frac{2}{1+ \frac{1}{1+2^{-1}}}- \frac{2}{1+ \frac{1}{1-2^{-1}}}= \frac{2}{1+ \frac{1}{1+ \frac{1}{2}}}- \frac{2}{1+ \frac{1}{1- \frac{1}{2}}}=\\\\= \frac{2}{1+ \frac{1}{ \frac{3}{2}}}- \frac{2}{1+ \frac{1}{ \frac{1}{2}}}= \frac{2}{1+ \frac{2}{3}}- \frac{2}{1+2}=\\\\= \frac{2}{ \frac{5}{3}}- \frac{2}{3}= \frac{6}{5}- \frac{2}{3}= \frac{18-10}{15}= \frac{8}{15}$