[tex]\bf \textit{unit vector of }\ \textless \ a,b\ \textgreater \ \implies \left( \cfrac{1}{||\ \textless \ a,b\ \textgreater \ ||} \right)\ \textless \ a,b\ \textgreater \ \\\\
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u=\ \textless \ -4,3\ \textgreater \ \qquad \textit{unit vector}\implies \left( \cfrac{1}{||\ \textless \ -4,3\ \textgreater \ ||} \right)\ \textless \ -4,3\ \textgreater \
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\left( \cfrac{1}{\sqrt{(-4)^2+(3)^2}} \right)\ \textless \ -4,3\ \textgreater \ \implies \cfrac{1}{\sqrt{25}}\ \textless \ -4,-3\ \textgreater \ \implies \cfrac{1}{5}\ \textless \ -4,3\ \textgreater \
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\left\ \textless \ \cfrac{-4}{5}\quad ,\quad \cfrac{3}{5} \right\ \textgreater \ \impliedby \textit{same angle, same direction}[/tex]
