If [tex]r^{\rightarrow} = bt^2i+ct^3j[/tex], where [tex]b[/tex] and [tex]c[/tex] are positive constants, when does the velocity vector make an angle of [tex]45.0^o[/tex] with the x- and y-axes?(adsbygoogle = window.adsbygoogle || []).push({});

i & j are vectors.

i have no clue on how to start it, can anyone give me a hint?

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# Velocity vector

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