Question

$frac{4}{y} - frac{2}{y-5}+ frac{2y+10}{25-y^{2} }$ Упростите выражение!

Answer 1

4/y+2/(5-y)+2y/(5-y)(5+y)=(100-4y²+10y+2y²+2y²+10y)/[y(25-y²)]=
=(20y+100)/[y(25-y²)]=20(y+5)/[y(5-y)(5+y)]=20/(5y-y²)