Matematika

Pertanyaan

tolong di bantu kak buat hari ini soalnya
tolong di bantu kak buat hari ini soalnya

1 Jawaban

  • 16.]
    (½)²ˣ⁺¹ > √[ 8 / 2ˣ⁻¹]
    (½)²ˣ⁺¹ > √[ 2³⁻⁽ˣ ⁻ ¹⁾]
    (½)²ˣ⁺¹ > √[ 2⁴⁻ˣ]
    (2)⁻²ˣ⁻¹ > 2^{½ (4 - x)}
    -2x - 1 > ½(4 - x)
    -2x - 1 > 2 - ½ x
    -³/₂ x > 3 [× -2]
    3x < -6
    x < -2
    [B]

    17.]
    log (x² + 9x + 5) = 1
    x² + 9x + 5 = 10
    x² + 9x - 5 = 0

    x₁ + x₂ = -b / a = -9
    [A]

    18.]
    log x + log(x - 3) = 1
    log x(x - 3) = log 10
    x² - 3x = 10
    x² - 3x - 10 = 0
    (x - 5)(x + 2) = 0
    x = -2 atau x = 5 ... (i)

    Syarat
    x - 3 > 0
    x > 3 ... (ii)

    Irisan dari (i) dan (ii) adalah HP-nya
    HP : { 5 }

    19.]
    log (∛2 × √2)
    = log ∛2 + log √2
    = log 2^{⅓} + log 2^{½}
    = (⅓ × log 2) + (½ × log 2)
    = (⅓ + ½) × log 2
    = ⅚ × 0,3010
    = 0,2508
    [ - ]

    20.]
    ²log 27 × ⁹log5 × ²⁵log ¹/₁₆
    = ²log 3³ × [tex] ^{3^2} \log 5 \times ^{5^2} \log 2^{-4} [/tex]
    = 3 × ²log 3 × ½ × ³log 5 × (-2) × ⁵log 2
    = -3 × ²log 2
    = -3
    [A]

    Koreksi jika mendapat kesalahan