д) 7(√2/7)² + 1/√12

д) $$7\left(\sqrt{\frac{2}{7}}\right)^2 + \frac{1}{\sqrt{12}} = 7 \cdot \frac{2}{7} + \frac{1}{2\sqrt{3}} = 2 + \frac{\sqrt{3}}{2 \cdot 3} = 2 + \frac{\sqrt{3}}{6}$$

Ответ: $$2 + \frac{\sqrt{3}}{6}$$