Đáp án:
\(\begin{array}{l}
a.\overrightarrow a = (2,0)\\
\overrightarrow b = (1, - 3)\\
\overrightarrow c = (5,4)\\
b.\overrightarrow d = (12,20)
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a.\\
\overrightarrow a = 2\overrightarrow i \to \overrightarrow a = (2,0)\\
\overrightarrow b = \overrightarrow i - 3\overrightarrow j \to \overrightarrow b = (1, - 3)\\
\overrightarrow c = 5\overrightarrow i + 4\overrightarrow j \to \overrightarrow c = (5,4)\\
b.\\
\overrightarrow d = 3\overrightarrow a - 4\overrightarrow b + 2\overrightarrow c \\
\to \left\{ \begin{array}{l}
x = 3.2 - 4.1 + 2.5 = 12\\
y = 3.0 - 4.( - 3) + 2.4 = 20
\end{array} \right. \to \overrightarrow d = (12,20)
\end{array}\)