There are two points on the 2D rectangular coordinate system, namely(adsbygoogle = window.adsbygoogle || []).push({}); PandM.

Their positions are function of time and are:

[tex]Position \, of \, P: \, (p_x(t), \, p_y(t))[/tex]

[tex]Position \, of \, M: \, (m_x(t), \, m_y(t))[/tex]

Distance between them is:

[tex]R(t) \, = \, \sqrt{(p_x - m_x)^2 \, + \, (p_y - m_y)^2}[/tex]

And the relative speed (magnitude of relative velocity) between them is:

[tex]V_{pm}(t) \, = \, - \frac{dR}{dt}[/tex]

Is it correct up to this step?

If so, can you please help me take this derivative?

If not, how do I calculate this relative speed?

Any help will be appreciated.

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# Trying to calculate relative speed between two moving points

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