This is actually not a full problem, just a part of one I'm having trouble with:(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

If I have a acceleration vector, say [ b[itex]k^{2}[/itex][itex]e^{kt}[/itex] - b[itex]c^{2}[/itex][itex]e^{kt}[/itex] ][itex]e_{r}[/itex] + [ 2bkc[itex]e^{kt}[/itex] ] [itex]e_{θ}[/itex]. How can I find its magnitude?

2. Relevant equations

Mag vector |a| = (a^2)^(1/2)

3. The attempt at a solution

As I square [itex]_{e}r[/itex], the cross term is still negative under the radical, and doesn't subtract cleanly:

[ [itex]b^{2}k^{4}e^{kt}[/itex] + [itex]b^{2}c^{4}e^{kt}[/itex] - 2[itex]b^{2}k^{2}c^{2}e^{kt}[/itex] ][itex]^{1/2}[/itex]

I'm either doing some wrong algebra or missing something obvious I think?

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# Homework Help: Magnitude of vector, negative in part.

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