Первый вариант раскрытия модуля:
х²-5х-24=0
D=(-(-5))²-4×1×(-24)=25+96=121
x1=(-(-5)-√121)/2×1=(5-11)/2=-6/2=-3;
x2=(-(-5)+√121)/2×1=(5+11)/2=16/2=8.
второй вариант раскрытия модуля:
х²+5х-24=0
По теореме Виета:
х1+х2=-5
х1×х2=-24
х1=3
х2=-8.
(8 5/7 - 6 5/6 ÷ 1 5/36) ÷ 4 3/4 =4/7
1)6 5/6 ÷ 1 5/36 = 41/6 ÷ 41/36 = 41/6 × 36/41 = 6
2)8 5/7 - 6 = 61/7 - 6 =(61 × 1 - 6 × 7)/7 = 61/7 - 42/7 = 19/7 = 2 5/7
3)2 5/7 ÷ 4 3/4 = 19/7 ÷ 19/4 = 19/7 × 4/19 = 4/7
(2 5/6 + 2 2/9) ÷ 3 1/4 - 2/7 ÷<span> 1 7/7 =1 26/63
1)</span>2 5/6 + 2 2/9 = 17/6 + 20/9 = (17 × 3 + 20 × 2)/18 = 51/18 + 40/18 = 91/18 = 5 1/18
<span>2)5 1/18 ÷ 3 1/4 = 91/18 ÷ 13/4 = 91/18 × 4/13 = 14/9 = 1 5/9
3)2/7 ÷ 1 7/7 = 2/7 ÷ 2 = 2/7 × 1/2 = 1/7
4)</span>1 5/9 - 1/7 = 14/9 - 1/7 =(14 × 7 - 1 × 9)/63 = 98/63 - 9/63 = 89/63 = 1 26/63
) 1,32:2=0,66
8,4:15=0,56
11,16:18=0,62