Matematika

Pertanyaan

Materi Fungsi Komposisi dan Fungsi Invers

Soal berupa lampiran

Jawab dengan penjelasan/langkah
Materi Fungsi Komposisi dan Fungsi Invers Soal berupa lampiran Jawab dengan penjelasan/langkah

1 Jawaban

  • Matematika (Fungsi komposisi dan invers)

    f(x) = (2x - 3) / (x + 2)

    y (x + 2) = 2x - 3
    2x - xy = 2y + 3
    x = (2y + 3) / (2 - y)
    f`¹(x) = (2x + 3) / (2 - x)

    g(x) = 2x - 1

    y = 2x - 1
    x = (y + 1) / 2
    gˉ¹(x) = (x + 1) / 2

    Nomor 1
    (fog)(x) = f{g(x)}
    y = (2g(x) - 3) / (g(x) + 2)
    y = (2(2x - 1) - 3) / (2x - 1 + 2)
    y (2x + 1) = 4x - 5
    4x - 2xy = y + 5
    x = (y + 5) / (4 - 2y)

    (fog)ˉ¹(x) = (x + 5) / (4 - 2x)

    Nomor 2
    (gof)(x) = g{f(x)}
    y = 2f(x) - 1
    y = 2((2x - 3) / (x + 2)) - 1
    y = (4x - 6 - (x + 2)) / (x + 2)
    y(x + 2) = 3x - 8
    3x - xy = 2y + 8
    x = (2y + 8) / (3 - y)

    (gof)ˉ¹(x) = (2x + 8) / (3 - x)

    Nomor 3
    (gˉ¹of)(x) = gˉ¹{f(x)}

    = (f(x) + 1) / 2
    = ((2x - 3) / (x + 2) + 1) / 2
    = (2x - 3 + x + 2) / 2(x + 2)
    = (3x - 1) / (2x + 4)

    Nomor 4
    (fogˉ¹)(x) = f{gˉ¹(x)]
    y = (2gˉ¹(x) - 3) / (gˉ¹(x) + 2)
    y = (2(x+1)/2 - 3) / ((x+1)/2 + 2)
    y = (x - 2) / (x + 5)/2
    y(x + 5) = 2(x - 2)
    xy + 5y = 2x - 4
    2x - xy = 5y + 4
    x = (5y + 4) / (2 - y)

    (fogˉ¹)ˉ¹(x) = (5x + 4) / (2 - x)

    Nomor 5
    (gofˉ¹)(x) = g{fˉ¹(x)}

    = 2fˉ¹(x) - 1
    = 2((2x + 3) / (2 - x)) - 1
    = (4x + 6 - (2 - x) / (2 - x)
    = (5x + 4) / (2 - x)

    Nomor 6
    (fˉ¹og)(x) = fˉ¹{g(x)]
    y = (2g(x) + 3) / (2 - g(x))
    y = (2(2x - 1) + 3) / (2 - (2x - 1))
    y = (4x + 1) / (3 - 2x)
    y(3 - 2x) = 4x + 1
    3y - 2xy = 4x + 1
    4x + 2xy = 3y + 1
    x = (3y + 1) / (4 + 2y)

    (fˉ¹og)ˉ¹(x) = (3x + 1) / (4 + 2x)

    Nomor 7
    (fˉ¹)ˉ¹(x) = f(x)
    = (2x - 3) / (x + 2)

    Nomor 8
    (g`¹)`¹(x) = g(x)
    = 2x - 1