So, suppose we have this great infinite fraction:
x = 1 + 1 + 1 + 1 + . . . 1 1 1
Which mathematical constant is x equal to?
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The fraction doesn't ever change, so that means we can say x = 1 + x 1
Multiplying by x on both sides gives us x 2 = 1 + x .
Subtracting x and then 1 from both sides will then give us the quadratic x 2 − x − 1 = 0 .
From this, we know a = 1 , b = − 1 , and c = − 1 .
Plugging this into the quadratic formula for x becomes this: x = 2 1 ± 5 . If we choose to add 1, we get this:
x = 2 1 + 5
Sound familiar? It should, because the above is also equal to phi, so ϕ is the answer!
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If we observe the problem closely,we can see that the whole question is embedded in itself.So we can write the problem as: x = 1 + x 1 Rearranging this, we get: x = 1 + x 1 → x 2 − x − 1 = 0 Putting in the respective values in the quadratic formula,we get; 2 ( 1 ) − ( − 1 ) ± ( − 1 ) 2 − 4 ( 1 ) ( − 1 ) 2 1 ± 1 + 4 2 1 ± 5 Now as the infinite continued fraction is positive,we discard the negative root and the answer is 2 1 + 5 .Now this number is a very special number;it is... T h e G o l d e n R a t i o ! ! ! Which is denoted by ϕ so answer is ϕ