Matematika

Pertanyaan

tolong kakak....
di bantu soal JMO 2007
tolong kakak.... di bantu soal JMO 2007

1 Jawaban

  • kuadratkan kedua ruas
    (x + 1/x)² = 1²
    x² + 2 + 1/x² = 1
    x² + 1/x² = -1
    kuadratkan lagi
    (x² + 1/x²)² = -1²
    x⁴ + 2 + 1/x⁴ = 1
    x⁴ + 1/x⁴ = -1

    (x⁴ + 1/x⁴) = -1²
    x^8 + 2 + 1/x^8 = 1
    x^8 + 1/x^8 = -1

    (x⁴ + 1/x⁴)(x² + 1/x²) = (-1)(-1)
    x^6 + x² + 1/x² + 1/x^6 = 1
    x^6 + (x² + 1/x²) + 1/x^6 = 1
    x^6 + (-1) + 1/x^6 = 1
    x^6 + 1/x^6 = 2

    (x^8 + 1/x^8)(x² + 1/x²) = (-1)(-1)
    x^10 + x^6 + 1/x^6 + 1/x^10 = 1
    x^10 + (x^6 + 1/x^6) + 1/x^10 = 1
    x^10 + (2) + 1/x^10 = 1
    x^10 + 1/x^10 = -1

    sampe sini ajah kayanya bisanya coba perhatiin dulu bener gak