1)Нок(15;20)=60
(20+20+20=60 60:15=4)
2)Нок(65;52)=5*2*2*13=260
65=5*13
52=2*2*13
По определению логарифма имеем 7х-1=3^3,7х-1=27,7х=28,х=4
P(x)=p1(x) - p2(x) + 3p3(x)
p1(x) = 2x^2 - 5x,
p2(x) = 3x^2 + 1,
p3(x) = x - 2
p(x) = (2x^2-5x) - (3x^2+1) + 3*(x-2) =
= 2x^2 - 5x - 3x^2 - 1 + 3x - 6 =
= (2x^2 - 3x^2) + (3x - 5x) - (1+6) =
= -x^2 - 2x - 5 =
= (-1) * (x^2 + 2x + 5) =
= (-1) * [(x+2)^2 + 1]
11/9*(1,8х-2 1/4у)-7,2*(11/8х+17/12у)=11/9*18/10х-11/9*9/4у-72/10х*11/8х-
72/10*19/12у=11/5х-11/4у-99/10х-114/10у=-77/10х-283/20у=-7,7х-14,15у
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