IOM 2021, Блиц — Задача 39

The Blitz-contest of IOM-2021

Условие

Determine the area of triangle $ABC$ if point $O$ is the origin of the coordinate system with basis unit vectors $\vec{i}$ and $\vec{j}$, the vector $\overrightarrow{OA} = -2\vec{i} + \vec{j}$, the vector $\overrightarrow{AB} = 5\vec{i} - 3\vec{j}$, the vector $\overrightarrow{AC}$ is parallel to the vector $\vec{i}$, and the scalar product $\overrightarrow{AB} \cdot \overrightarrow{BC} = 0$.

If the answer is a fraction, it can be entered either as a decimal fraction or as a ratio “$r/s$”. Rounding is not allowed.

Отговори

Решение

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Оригинал в Архива: iom-2021-blitz-tasks-eng.pdf · официални решения: iom-2021-blitz-answers-eng.pdf