arsetpopeye
25log(x-3) + 25log(x+1) ≤ 1/2 25log (x - 3)(x + 1) ≤ 25log25^1/2 25log (x^2 - 2x - 3) ≤ 25log5 x^2 - 2x - 3 ≤ 5 x^2 -2x - 8 ≤ 0 (x - 4)(x + 2) ≤ 0 x = 4 atau x = -2 ......... (1) syarat x - 3 > 0 maka x > 3 ....... (2) x + 1 > 0 maka x > -1 ........ (3)
garis bilangannya (1) +++++++++ (-2) -------------- (4) +++++ (HP daerah yg negatif) (2) ------------------------------(3)+++++++++ (HP daerah yg positif) (3) ----------------------(-1) +++++++++++++ (HP daerah yg positif) Dr 3 garis bilangan maka HP urusannya = 3 < x ≤ 4
25log (x - 3)(x + 1) ≤ 25log25^1/2
25log (x^2 - 2x - 3) ≤ 25log5
x^2 - 2x - 3 ≤ 5
x^2 -2x - 8 ≤ 0
(x - 4)(x + 2) ≤ 0
x = 4 atau x = -2 ......... (1)
syarat
x - 3 > 0 maka x > 3 ....... (2)
x + 1 > 0 maka x > -1 ........ (3)
garis bilangannya
(1) +++++++++ (-2) -------------- (4) +++++ (HP daerah yg negatif)
(2) ------------------------------(3)+++++++++ (HP daerah yg positif)
(3) ----------------------(-1) +++++++++++++ (HP daerah yg positif)
Dr 3 garis bilangan maka HP urusannya = 3 < x ≤ 4