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The area, enclosed by the curves $$y = \sin x + \cos x$$ and $$y = |\cos x - \sin x|$$ and the lines $$x = 0$$, $$x = \frac{\pi}{2}$$, is:
Given curves,
$$y=\sin x+\cos x$$
and
$$y=|\cos x-\sin x|$$
for
$$0\le x\le\frac\pi2$$
Now,
$$\cos x-\sin x\ge0$$
for
$$0\le x\le\frac\pi4$$
Hence,
$$|\cos x-\sin x|=\cos x-\sin x$$
Also,
$$\cos x-\sin x<0$$
for
$$\frac\pi4\le x\le\frac\pi2$$
Hence,
$$|\cos x-\sin x|=\sin x-\cos x$$
Therefore, area is
$$\int_0^{\pi/4}\left[(\sin x+\cos x)-(\cos x-\sin x)\right]dx$$
$$+\int_{\pi/4}^{\pi/2}\left[(\sin x+\cos x)-(\sin x-\cos x)\right]dx$$
Simplifying,
$$=\int_0^{\pi/4}2\sin x\,dx+\int_{\pi/4}^{\pi/2}2\cos x\,dx$$
Now,
$$\int_0^{\pi/4}2\sin x\,dx=2[-\cos x]_0^{\pi/4}$$
$$=2\left(1-\frac1{\sqrt2}\right)$$
Also,
$$\int_{\pi/4}^{\pi/2}2\cos x\,dx=2[\sin x]_{\pi/4}^{\pi/2}$$
$$=2\left(1-\frac1{\sqrt2}\right)$$
Hence total area is
$$4\left(1-\frac1{\sqrt2}\right)$$
$$=4-2\sqrt2$$
Therefore, the required area is
$$\boxed{4-2\sqrt2}$$
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