this is part of the set @the Radicals \[\] let there be a infinite Radical \[ \sqrt{17+2\sqrt{88+24\sqrt{17+2\sqrt{88+24\sqrt{\dots\dots }}}}}\] it can be written as \[\sqrt{3^2+2^2+2^2+2\sqrt{(3\times2)^2+(2\times 2)^2 +(3\times 2)^2 +2(3\times 2\times 2)\sqrt{\dots\dots }}}\] then we can say that \[ \sqrt{17+2\sqrt{88+24\sqrt{17+2\sqrt{88+24\sqrt{\dots\dots }}}}}=7\] how??? lets see\[\] let \[F(a,b,c)=a+b+c\] \[F(a,b,c)=\sqrt{a^2 +b^2+c^2 +2(ab+bc+ca)}\] \[F(a,b,c)=\sqrt{a^2 +b^2 +c^2 +2\sqrt{(ab)^2+(bc)^2+(ca)^2+2(a^2bc+ab^2c+abc^2)}}\] \[F(a,b,c)=\sqrt{a^2 +b^2 +c^2 +2\sqrt{(ab)^2+(bc)^2+(ca)^2+2abc(a+b+c)}}\] now we can expand \(a+b+c\) like before and make it an infinite radical\[\] so we can say that\[\sqrt{a^2 +b^2 +c^2 +2\sqrt{(ab)^2+(bc)^2+(ca)^2+2abc\sqrt{a^2 +b^2 +c^2 +2\sqrt{(ab)^2+(bc)^2+(ca)^2+2abc\sqrt{\dots\dots}}}}} =a+b+c\]
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x+a=3(x+a)3x+a=3x3+3ax2+3a2x+a3x+a=3x3+2ax2+ax2+3a2x+a3x+a=3ax2+3a2x+a3+x3+2ax2x+a=3a(x2+3ax+a2)+x2(x+2a) In the same way get x+2a=32a(x2+3(2a)x+(2a)2)+x2(x+4a) and x+4a=34a(x2+3(4a)x+(4a)2)+x2(x+8a) and the expressions for x+8a,x+16aetc.Replacing all of these in the original expression we get: x+a=3a(x2+3ax+a2)+x232a(x2+3(2a)x+(2a)2)+x234a(x2+3(4a)x+(4a)2)+x23⋯to∞ VOILA!!!
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Please comment @Aareyan Manzoor
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ok, i find these seriously fascinating, the one by you is 1 of many. it is really good as well, let me show you another a+b=3a3+b3+3ab(a+b) a+b=3a3+b3+3ab3a3+b3+3ab3a3+b3+3ab3……
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x=1+(x−1)(x+1)=1+(x−1)1+x(x+2)=1+(x−1)1+x1+(x+1)(x+3)=1+(x−1)1+x1+(x+1)1+(x+2)(x+4) Continuing this indefinitely we get: x=1+(x−1)1+x1+(x+1)1+(x+2)⋯
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ax+(a+n)2+xax+(a+n)2+(x+n)……=x+n+a
already taken by ramnujanLog in to reply
nice one
Please note that just because something continues ad infinitum, you cannot add the inf symbol there. That'd mean you're literally having the hyperreal number infinity in the expresssion
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thanks, by the way, what is a hyperreal number,sir?
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Hyperreal Numbers (denoted ∗R is an extension of Real Numbers to accomodate infinite and infinitesimal numbers. It's an interesting idea, you could look it up.
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