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Problem

PlanetMaster

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Given x=6+6+6+...x = \sqrt{6 + \sqrt{6 + \sqrt{6 + ...}}}
We can rewrite this as x=6+xx = \sqrt{6 + x} as its iterating infinitely.

Squaring both sides and equating to zero
x2x6=0x^{2}-x-6=0
x23x+2x6=0x^{2}-3x+2x-6=0
x(x3)+2(x3)=0x(x-3)+2(x-3)=0
(x3)(x+2)=0(x-3)(x+2)=0
x=3,2x=3,-2

Therefore the answer is (b) 3 as we can't root a negative value.
 
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The answer is 6.
for full solution just ask me.
 
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