1) 5x – 8 > 3x – 6 [ x > 1 ]2) 7x – 3 + 5(-2x + 1) < 3x – 7 [ x > 3/2 ]3) (x + 1)(x2 – x + 1) + (x + 1)2 – 5x > 5(1 – x) + x2 (1 + x) + 2 [ x > 5/2 ]4) [(3x – 2) / 5] + [(5x – 6) / 15] + [(x – 3) / 10] – [(x – 3) / 30] ≥ 0 [ x ≥ 1]5) x2 + 3(x + 1) > (x + 3)2 – 3(x + 2) [non esiste alcuna x appart. ad R]6) 10x2 + 4x – (½) ≤ 0 [ - ½ ≤ x ≤ 1/10 ]7) x2 – (5/3)x – 2/3 ≤ 0 [ - 1/3 ≤ x ≤ 2 ]8) (x2 / 3) + (4/3)x – 7 < 0 [ -7 < x < 3 ][a cura di Walter Caputo - 07-10-2008]
ESERCIZIO 7 PER STUDENTI 3^ IGEA: Disequazioni
1) 5x – 8 > 3x – 6 [ x > 1 ]2) 7x – 3 + 5(-2x + 1) < 3x – 7 [ x > 3/2 ]3) (x + 1)(x2 – x + 1) + (x + 1)2 – 5x > 5(1 – x) + x2 (1 + x) + 2 [ x > 5/2 ]4) [(3x – 2) / 5] + [(5x – 6) / 15] + [(x – 3) / 10] – [(x – 3) / 30] ≥ 0 [ x ≥ 1]5) x2 + 3(x + 1) > (x + 3)2 – 3(x + 2) [non esiste alcuna x appart. ad R]6) 10x2 + 4x – (½) ≤ 0 [ - ½ ≤ x ≤ 1/10 ]7) x2 – (5/3)x – 2/3 ≤ 0 [ - 1/3 ≤ x ≤ 2 ]8) (x2 / 3) + (4/3)x – 7 < 0 [ -7 < x < 3 ][a cura di Walter Caputo - 07-10-2008]