b0b: bobo

Bob:Substitutex=cos\alp,\alp∈[0:;π] \displaystyle Then\; |x+\sqrt{1-x^2}|=\sqrt{2}(2x^2-1)\Leftright |cos\alp +sin\alp |=\sqrt{2}(2cos^2\alp -1)Then∣x+ 1−x 2 ​ ∣= 2 ​ (2x 2 −1)\Leftright∣cos\alp+sin\alp∣= 2 ​ (2cos 2 \alp−1) \displaystyle |\N {\sqrt{2}}cos(\alp-\frac{\pi}{4})|=\N {\sqrt{2}}cos(2\alp )\Right \alp\in[0\: ;\: \frac{\pi}{4}]\cup [\frac{3\pi}{4}\: ;\: \pi]∣N 2 ​ cos(\alp− 4 π ​ )∣=N 2 ​ cos(2\alp)\Right\alp∈[0; 4 π ​ ]∪[ 4 3π ​ ;π] 1) \displaystyle \alp \in [0\: ;\: \frac{\pi}{4}]\alp∈[0; 4 π ​ ] \displaystyle cos(\alp -\frac{\pi}{4})=cos(2\alp )\dotscos(\alp− 4 π ​ )=cos(2\alp)… 2. \displaystyle \alp\in [\frac{3\pi}{4}\: ;\: \pi]\alp∈[ 4 3π ​ ;π] \displaystyle -cos(\alp -\frac{\pi}{4})=cos(2\alp )\dots−cos(\alp− 4 π ​ )=cos(2\alp)…

bobs very smart

don't worry bobs passive unless you touch him . . .