Question

СРОЧНООО!!!!!!!!!ПЛИИИЗ
1)$frac{4a^{2} }{(a+b)^{2}+2( a^{2}-b^{2})+(a-b)^{2} } =1$

2)$( frac{a^{2} }{a+n} - frac{a^{2}}{a^{2}+n^{2}+2an } ): ( frac{a^{2} }{a-n} - frac{ a^{2} }{a^{2}- n^{2} } )$