Matematika

Pertanyaan

Nilai dari suku banyak f(x) = X^3 + 6x^2 - X + 7 untuk nilai X = m-2 adalah .. tolong bantu plis.. makasih

2 Jawaban

  • x = m - 2

    f(x) = (m-2)³ + 6(m-2)² - m -2 + 7
    f(x) = m³ - 6m + 8 + 6 (m² - 4m + 4) - m + 5
    f(x) = m³ + 6m² -31m + 23
  • f(x) = x^3 + 6x^2 - x + 7
    f(m - 2) = (m - 2)^3 + 6(m - 2)^2 - (m - 2) + 7
    = (m - 2)(m - 2)^2 + 6(m - 2)^2 - m + 2 + 7
    = (m - 2)(m^2 - 4m + 4) + 6(m^2 - 4m + 4) - m + 9
    = (m^3 - 4m^2 + 4m - 2m^2 + 8m - 8) + 6m^2 - 24m + 24 - m + 9
    = m^3 - 6m^2 + 12m - 8 + 6m^2 - 25m + 33
    = m^3 - 13m + 25

    Cara Horner
    (m - 2) | 1 .... 6 ............ -1 ......................... 7
    ............ | ...... m - 2 ..... m^2 + 2m - 8 .... m^3 - 13m + 18
    --------------------------------------------------------------------------- +
    ............. 1 ... m + 4 ..... m^2 + 2m - 9 ..|.. m^3 - 13m + 25 => f(m - 2)
    Jadi f(m - 2) = m^3 - 13m + 25

Pertanyaan Lainnya