3Y^2 + 8Y + 4 = 0
D = 64 - 4*3*4 = 64 - 48 = 16
V D = 4
X1 = ( - 8 + 4 ) : 6 = ( - 4/6 ) = ( - 2/3 )
X2 = ( - 12 ) : 6 = ( - 2 )
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-6X^2 + 13X - 6 = 0
D = 169 - 4*(-6)*(-6) = 169 - 144 = 25
V D = 5
X1 = ( - 13 + 5 ) : ( - 12 ) = + 8/12 = 4/6 = 2/3
X2 = ( - 18 ) : ( - 12 ) = + 1.5
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X^4 - 13X^2 + 36 = 0
X^2 = A ( A > 0 )
A^2 - 13A + 36 = 0
D = 169 - 4*1*36 = 169 - 144 = 25
V D = 5
A1 = ( - 1 + 5 ) : 2 = 2
A2 = ( - 6 ) : 2 = ( - 3 ) ( < 0 )
X^2 = 2 ---> X = V 2
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1) 5(2a+3b)
2) b(2a-5)
3) x4(x-1)
4) 2m3(m3+4)
5) 3y(xy+2)
6) Bc(5c+1)
7) Ab(ab-4b2+6a2)
8) (3-x)(b-4)
9) (a-b)(5-x)
10) 3a3b2(3b3-2a2)
11) 5xy2(2-3x+5x5y)
12) (x-4)(x-5)
13) 2n3(2+n)(n+3)
{5х+2у=4
{2х+у=1|*2
-{5x+2y=4
-{4x+2y=2
x=2
2*2+y=1
y=1-4
y=-3
Сn =c1+d(n-1) cn=-24+1.6(n-1)
cn>0 -24+1.6n-1.6>0 1.6n>25.6 n>25.6/1.6=16
ответ с17
мы не берем n=16 при таком значении с16=0 а нам нужно строго cn>0
Ответ: (1/6)^(-5/6)=1:((1/6)^(5/6))=6^(5/6) больше 1.
Объяснение: