[tex]\dfrac{1}{f}=\dfrac{1}{x_1}+\dfrac{1}{x_2} \ \ \ \ \ \Rightarrow \ \ \ \ x_2=\dfrac{1}{\dfrac{1}{f}-\dfrac{1}{x_1}}. \\ \\ \\ \\ \dfrac{y_2}{y_1}=\dfrac{x_2}{x_1} \ \ \ \ \ \ \Rightarrow \ \ \ \ \ y_2=\dfrac{x_2y_1}{x_1}[/tex]
Datele sunt:
[tex]f=-0.1 \\ y_1=0.2 \\ x_1=-0.3[/tex]
