Matematika

Pertanyaan

Penyelesaian pertidaksamaan 2x^-x+3 PER X^-2X-3 >4 adalah.....
Penyelesaian pertidaksamaan 2x^-x+3 PER X^-2X-3 >4 adalah.....

1 Jawaban

  • (2x² - x + 3)/(x²-2x-3) - 4 > 0
    (2x²-x+3)/(x²-2x-3) - 4(x²-2x-3)/(x²-2x-3) > 0
    (2x²-x+3)/(x²-2x-3) - (4x²-8x-12)/(x²-2x-3) > 0
    (2x²-x+3-4x²+8x+12) / (x²-2x-3) > 0
    (-2x²+7x+15) / (x²-2x-3) > 0
    (-2x - 3)(x - 5) / (x - 3)(x + 1) > 0
    buat garis bilangan di
    -2x - 3 = 0
    -2x = 3
    x = -3/2 = -1½
    x = 5
    x = 3
    x = -1
    - - - - - + + + + - - - - - - + + + + - - - -
    --------•---------•----------•---------•----------
    `````` -1½ ``````` -1 ````````````3 ````````` 5
    hp
    -1½ < x < -1 atau 3 < x < 5