Сократите дроби: а) \(\frac{16b}{20b^4}\); б) \(\frac{4x-16}{x^2-16}\); в) \(\frac{12y^3-8y^2}{2-3y}\).

1. \(\frac{16b}{20b^4}=\frac{4\cdot4b}{4\cdot5b^4}=\frac{4}{5b^3}\), \(b\ne0\).
2. \(\frac{4x-16}{x^2-16}=\frac{4(x-4)}{(x-4)(x+4)}=\frac{4}{x+4}\), \(x\ne\pm4\).
3. \(\frac{12y^3-8y^2}{2-3y}=\frac{4y^2(3y-2)}{-(3y-2)}=-4y^2\), \(y\ne\frac{2}{3}\).

Ответ: а) \(\frac{4}{5b^3}\); б) \(\frac{4}{x+4}\); в) \(-4y^2\).