1. (49x² + 14x + 1) : 7x+1/4x =

1. Преобразуем выражение:

$$ (49x^2 + 14x + 1) : \frac{7x+1}{4x} = $$

$$ = (7x+1)^2 : \frac{7x+1}{4x} = $$

$$ = \frac{(7x+1)^2 \cdot 4x}{7x+1} = $$

$$ = 4x(7x+1) = $$

$$ = 28x^2 + 4x $$

Ответ: 28x² + 4x