Kuncisoal mtk un smk prwsta

1.

Jawaban: C
( x 2 + 1) 2 − 12( x 2 + 1) + 20 ≤ 0
x4 + 2x2 + 1 – 12x2 – 12 + 20 ≤ 0
x4 – 10x2 + 9 ≤ 0
(x2 – 1)(x2 – 9) ≤ 0
(x + 1)(x – 1)(x + 3)(x – 3) ≤ 0

−

+

+

−

+

−3

−1
1
3
−3 ≤ x ≤ −1 atau 1 ≤ x ≤ 3

2.

Jawaban: D
2x 2 + x − 3