Ответ:

Объяснение:

1) {[(x + 4)² - (x - 4)²] /(x² - 16)}  * [(16 - x²)/16x³] =

(x + 4 + x - 4)(x + 4 -x + 4) /(x² - 16)  * [(16 - x²)/16x³] =

=[ -16x/(16 - x²)] *[(16 - x²)/16x³] = - 1/x²

2) [3y/(y - 1)] - [(y + 3)/5(y - 1)] *[15/y(y + 3)] =

= [3y/(y - 1)]- 3/y(y - 1) = (3y² - 3)/y(y - 1) =

= 3(y² - 1) /y(y - 1) =  3(y -1)(y + 1)/y(y - 1) = 3(y + 1)/y = (3y + 3)/y