Constructing a Sequence for Pointwise Convergence and Unboundedness

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Give an example of a sequence \{ f_n\} of continuous functions defined on [0,1] such that \{ f_n\} converges pointwise to the zero function on [0,1], but the sequence \{ \int^{1}_{0} f_n\} is unbounded.

I'm pretty lost on this one.
 
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Hint: Try coming up with a sequence of functions such that ##f_n(x)## is only nonzero on the interval ##(0, 1/n)##. You will need to make them grow "taller" and "narrower" as ##n## increases.
 

Thread 'Prove that the integral is equal to ##\pi^2/8##'

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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