Упростите данные выражения.1) 2)

$( \frac{a}{a+1} +1):(1- \frac{3a ^{2} }{1-a ^{2} })$ = $\frac{1-a}{1-2a}$

$( \frac{a}{a+1} +1)= \frac{a+a+1}{a+1} = \frac{2a+1}{a+1}$

$(1- \frac{3a ^{2} }{1-a ^{2} }) = \frac{1- a^{2}-3 a^{2} }{1- a^{2} } = \frac{2a+1}{a+1} :\frac{1-4a^{2} }{1- a^{2} } =\frac{2a+1}{a+1}* \frac{(1-a)(1+a)}{(1-2a)(1+2a)} = \frac{1-a}{1-2a}$

$( \frac{2m+1}{2m-1} - \frac{2m-1}{2m+1} ): \frac{4m}{10m-5}$ = $\frac{10}{2m+1}$

$( \frac{2m+1}{2m-1} - \frac{2m-1}{2m+1} )= \frac{(2m+1) ^{2}-(2m-1) ^{2} }{(2m-1)(2m+1)} =$ $\frac{4 m^{2} +4m+1-4 m^{2}+4m -1 }{(2m-1)(2m+1)} = \frac{8m}{(2m-1)2m+1) }$

$\frac{8m}{(2m-1)(2m+1) } : \frac{4m}{10m-5} =\frac{8m}{ (2m-1)(2m+1)} * \frac{5(2m-1)}{4m}$ = $\frac{10}{2m+1}$