4 2/7 - 1 4/9 = 30/7 - 13/9 = (270 - 91) / 63 = 179 / 63 = 2целых 53/63
8 3/4 × 1 3/14 = 35/4 × 17/14 = 595 / 56 = 10,625
1 9/5 ÷ 5 1/3 = 14/5 ÷ 16/3 = 14/5 × 3/16 = 21 / 40 = 0,525
(2 * sin10 * cos10 * cos 20) : (cos 50) = sin 20 * cos 20 / cos 50 =
x≠1, x>0, x≠0 х>1
log6 x= log6 6 - log6(x-1)
log6 x= log6 (6/(x-1))
x=6/(x-1)
x²-x-6=0
d=1+24=25
x=(1+-5)/2
x=3
x=-2 <span>ответ: 3</span>