Решите пожалyйста ,Упростите выражение 4xy ( 1 1 ) \\\\\\\: ( \\\\\\\\\ + \\\\\\\\\\\ ) y²-x² ( y²-x² x²+2xy+y²)

1)(x+y)/(x-y) - (x-y)/(x+y)=(x²+2xy+y²-x²+2xy-y²)/(x²-y²)=4xy/(x²-y²) 2)4xy/(x²-y²) : xy/(x²-y²)=4xy/(x²-y²) *(x²-y²)/xy=4