Ответ:

  1. \(\frac{9c^2-16}{16-24c+9c^2}=\frac{(3c-4)(3c+4)}{(3c-4)^2}=\frac{3c+4}{3c-4}\).
  2. \(\frac{16x^2-24xy+9y^2}{9y^2-16x^2}=\frac{(4x-3y)^2}{(3y-4x)(3y+4x)}=\frac{3y-4x}{3y+4x}\).
  3. \(\frac{4x^2-4xy+y^2}{y^2-4x^2}=\frac{(2x-y)^2}{(y-2x)(y+2x)}=\frac{y-2x}{y+2x}\).
  4. \(\frac{36c-c^3}{c^3+12c^2+36c}=\frac{c(6-c)(6+c)}{c(c+6)^2}=\frac{6-c}{c+6}\).
  5. \(\frac{25b-49b^3}{49b^3-70b^2+25b}=\frac{b(5-7b)(5+7b)}{b(7b-5)^2}=\frac{5+7b}{5-7b}\).
  6. \(\frac{4b^2-12bc+9c^2}{-2ab+3ac}=\frac{(2b-3c)^2}{a(3c-2b)}=\frac{3c-2b}{a}\).

Ответ: 1) \(\frac{3c+4}{3c-4}\); 2) \(\frac{3y-4x}{3y+4x}\); 3) \(\frac{y-2x}{y+2x}\); 4) \(\frac{6-c}{c+6}\); 5) \(\frac{5+7b}{5-7b}\); 6) \(\frac{3c-2b}{a}\).