How to Integrate 1-cos(t)dt and Prove the Resulting Derivative

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Homework Statement



it's been a long summer and i forgot everything.
i need help integrating 1-cos(t)dt

evaluate g(x) = [\pi,x]integral (1-cos(t))dt

i know by pt2 of fund. thm of calc that g' (x) = 1-cos(x)
but i can't remember how to evaluate the integral and then differentiate to prove my answer.\
I should just know the integral of 1-cosx but I'm retarded and forgot what to do.
any help?
 
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Well you know that by the properties of integrals, you can treat it as two integrals
I=I_1+I_2=\left(\int 1dt\right)+\left(-\int\cos{t}dt\right)
Do you know these integrals? What is the derivative of -\sin{t}?
 
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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