Ta có: cos45° = $\frac{|$\overrightarrow{F2}$|}{a}$ => | $\overrightarrow{F2}$ | = | $\overrightarrow{F}$ | . cos45° = $\frac{a√2}{2}$
sin45° = $\frac{|$\overrightarrow{F1}$|}{a}$ => |$\overrightarrow{F1}$| = | $\overrightarrow{F}$ | . sin45° = $\frac{a√2}{2}$