Question

cu proprtii derivate va rog​

Answer 1

Explicație pas cu pas:

b)

$\dfrac{x}{y} = \dfrac{4}{5} \iff \dfrac{3 \cdot x}{2 \cdot y} = \dfrac{3 \cdot 4}{2 \cdot 5} \\ \dfrac{3x}{2y} = \dfrac{12}{10} \iff \dfrac{3x + 2y}{2y} = \dfrac{12 + 10}{10} \\ \dfrac{3x + 2y}{2y} = \dfrac{22}{10} \implies \dfrac{3x + 2y}{2y} = \dfrac{11}{5}$

c)

$\dfrac{x}{y} = \dfrac{2}{7} \iff \dfrac{5 \cdot x}{3 \cdot y} = \dfrac{5 \cdot 2}{3 \cdot 7} \\ \dfrac{5x}{3y} = \dfrac{10}{21} \iff \dfrac{5x}{3y - 5x} = \dfrac{10}{21 - 10} \\ \implies \dfrac{5x}{3y - 5x} = \dfrac{10}{11}$