Matematika

Pertanyaan

|x-3|^2-8|x-3|>-12 Tolong di jawab :)
|x-3|^2-8|x-3|>-12 Tolong di jawab :)

2 Jawaban

  • Pertdksamaan NiLai MutLak

    Misal :
    |x - 3| = a

    |x - 3|² - 8|x - 3| > -12
    a² - 8a + 12 > 0
    (a - 2)(a - 6) > 0
    a < 2 atau a > 6


    Utk a < 2
    |x - 3| < 2
    -2 < x - 3 < 2
    -2 + 3 < x < 2 + 3
    1 < x < 5 ... (1)


    Utk a > 6
    |x - 3| > 6
    x - 3 > 6
    x > 9 .. (2)

    x - 3 < -6
    x < -3 ... (3)

    Nilai x yg memenuhi :
    x < -3
    x > 9
    1 < x < 5

  • |x-3|^2-8|x-3|>-12
    (x-3)^2-8(x-3)>-12
    x^2-6x+9-8x+24>-12
    x^2-14x+33>-12
    x^2-14x+33+12>0
    x^2-14x+45>0
    (x-9)(x-5)>0
    x-9>0 atau x-5<0
    x>9 atau x<5

    (x-3)^2+8(x-3)>-12
    x^2-6x+9+8x-24>-12
    x^2+2x-15>-12
    x^2+2x-15+12>0
    x^2+2x-3>0
    (x+3)(x-1)>0
    x+3<0 atau x-1>0
    x<-3 atau x>1
    Jadi HPnya adalah {x>9 , x<-3 , 1<x<5}