д) 4√1/49 11/5 a⁴b⁶ при а = −2, b = 3,5;

д) $$4 \cdot \sqrt{\frac{1}{49} \cdot \frac{11}{5}a^4b^6} = 4 \cdot \frac{1}{7} \cdot a^2 \cdot |b^3| \cdot \sqrt{\frac{11}{5}} = \frac{4}{7} \cdot a^2 \cdot |b^3| \cdot \sqrt{\frac{11}{5}} $$.

При $$a = -2, b = 3.5$$, получим:

$$\frac{4}{7} \cdot (-2)^2 \cdot |3.5^3| \cdot \sqrt{\frac{11}{5}} = \frac{4}{7} \cdot 4 \cdot (3.5)^3 \cdot \sqrt{\frac{11}{5}} = \frac{16 \cdot 42.875}{7} \cdot \sqrt{\frac{11}{5}} = \frac{686}{7} \cdot \sqrt{\frac{11}{5}} = 98 \cdot \sqrt{\frac{11}{5}} = 98 \cdot \frac{\sqrt{55}}{5} $$.

Ответ: $$98 \cdot \frac{\sqrt{55}}{5}$$