MarD.
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MarD. asked in Science & MathematicsGeography · 7 years ago

what is one number whose reciprocal is one less than itself?

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  • 7 years ago
    Favorite Answer

    x = 1/x + 1

    x² = 1 + x

    x² – x – 1 = 0 quadratic formula

    two solutions

    x = 1.618 or x = – 0.61803

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  • 7 years ago

    " ? " has beaten me by 18 minutes. He gave the exact answer. The (irrational) number is called 'Phi',

    φ = ½ [√5±1].

    Further the square of the number is 'one more than itself'. That is

    φ² = φ + 1 = 2.6180.

    The equation stems from what ' ? ' derived.

    In Trigonometry, functions of multiples of 18º (= π/10) are expressed as functions involving φ,

    Sin [n(π/10)], Cos [n(π/10)] = f(φ).

    It has several more Mathematical uses & is a hot favourite of 'Architects' who call it 'Magic number'. A rectangle of these proportions is the most aesthetic in architecture (le Corbusier used it extensively in proportioning his buildings in his town planning of a new city - Chandigarh).

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  • 7 years ago

    Camel

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