Arc Length in Parametric equation

perpetium
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I know this is very simple, but the end integral just kills me

Homework Statement


Given equation in Parametric form
x=\sqrt{2t+1}), y=6t
Find arc length

Homework Equations


The Attempt at a Solution


take x' & y'
then Take integral of \int\sqrt{1/(2t+1) + 36}

This is where I got stuck ...is there a simple way to solve this integral ?
Thank you
 
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You didn't specify the limits of t for which the arc length is to be evaluated. You can try an alternatve approach here. Note that you can easily express the graph in the form y = f(x). Do that, and use the other formula to calculate arc length. Should be easier to integrate. Also remember to find the values of x for which the arc length is to be calculated.
 
Defennder thanks for response
I have already evaluated that integral in the y=f(x) form, through trigonometric substitution

Now I need to evaluate it in parametric form...
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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