Continuety of sum of functions

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A.does f(x) +g(x) continues in X0 when
f(x) continues in X0 but g(x) doesnt?

B.does f(x) +g(x) continues in X0 when both
f(x) and g(x) are not continues in X0?

prove and give exmple to support your answer

??
 
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If you're uncertain whether or not each function is continuous, try to constuct a counter example satisying the initial premises. After that, prove whatever result you obtained.
 
For b) consider functions that have discont. but for example sum to be some constant.
 
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i don't know how to prove such things
??
 
Are you sure you are supposed to prove them? b) is false using the example I gave so come up with a counterexample using the logic that I told you
 
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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