\(\overrightarrow{AB}=\left(100;200;1250\right)=\left(2;4;25\right)=\overrightarrow{u}\)
\(\left(Oxy\right):z=0\Rightarrow\overrightarrow{n}=\left(0;0;1\right)\)
\(\alpha=\left(\widehat{\overrightarrow{u};\overrightarrow{n}}\right)\)
\(cos\left(\widehat{\overrightarrow{u};\overrightarrow{n}}\right)=\dfrac{\left|0.2+0.4+1.25\right|}{\sqrt{2^2+4^2+25^2}.\sqrt{0^2+0^2+1^2}}=\dfrac{25}{\sqrt{645}}\)
\(\Rightarrow\alpha=\left(\widehat{\overrightarrow{u};\overrightarrow{n}}\right)=arcos\left(\dfrac{25}{\sqrt{645}}\right)\)
Góc giữa phương chuyển động và mặt đất là góc \(\beta=90^o-\alpha\)
\(\Rightarrow\beta=90^o-arcos\left(\dfrac{25}{\sqrt{645}}\right)=90^o-10,1^o=79,9^o\)
