1
28(5+3√2)/(5-√18)(5+√18)=28(5+3√2)/(25-18)=28(5+3√2)/7=4(5+3√2)
2
9(∛2+1)/(∛2+1)(∛4-∛2+1)=9(∛2+1)/(2+1)=9(∛2+1)/3=3(∛2+1)
Это элементарное возведение в степень 2^4=2•2•2•2=16
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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1.127:
1)3.4*10^11>7.5*10^9
2)3,4*10^-11<7,5*10^-9( если не ошибаюсь )
3)7,27*10^(−5)<7,27*10^(−4)
4)9,2*10^(-7)<3,2*10^4