Derivative of x: Taking Derivatives of \sqrt{(10t-3)^{2} + (2t)^{2}}

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Homework Statement



x = \sqrt{(10t-3)^{2} + (2t)^{2}}

Find the derivative

Homework Equations





The Attempt at a Solution



x = \sqrt{(10t-3)^{2} + (2t)^{2}}

x = \sqrt{(104t^{2} - 60t + 9}

dx = \frac{1}{2\sqrt{104t^{2} - 60t + 9}}(208t-60)

dx = \frac{208t-60}{2\sqrt{104t^{2} - 60t + 9}}

 
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That's correct. :smile:

You can divide both nominator and denominator with 2.
 
But what you computed isn't dx. In your equations you should have

dx/dt = your answer.
 
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