[tex]\vec{r}(t)=[t+1,4t^2-3]\\x(t)=t+1\ \Rightarrow\ t=x-1\\y(x)=4(x-1)^2-3\\y(x)=4x^2-8x-2=2(x^2-4x-1)[/tex]
[tex]\vec{V}(t)=\dot{\vec{r}}=[1,8t]\\|\vec{V}|=\sqrt{1+64t^2}[/tex]
[tex]\vec{a}(t)=\ddot{\vec{r}}=[0,8]\\|\vec{a}|=8[/tex]
[tex]\vec{V}(t=2s)=[1,16]\\|\vec{V}(t=2s)|=\sqrt{257}\approx16.03\frac{m}{s}\\\vec{a}(t=2s)=[0,8]\\|\vec{a}(t=2s)|=8\frac{m}{s^2}[/tex]
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