Ac-ad-5bc+5bd=(ac -ad)+(-5bc+5bd)=a(c-d )-5(c-d)=(c-d)(a-5)
Я, конечно, сомневаюсь, но, вроде, 0,6.
<span>5х-2(х-3)=6х
</span>5х-2х+6=6х
5x-2x-6x = -6
- 3x = -6
x = -6:-3
x = 2
<span>6х-(2х-5)=2(3х-6)
</span>6x-2x+5 = 6x-12
6x-2x-6x = -12 -5
-2x = -17
x = -17:-2
x = 8.5
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x^2+y^2 =2
y=x
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x^2+x^2=2
y=x
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2x^2=2
y=x
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x^2=1
y=x
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x первое= +1
y первое= +1
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x второе = -1
y второе = -1
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(1;1) (-1;-1)
Lgx≠5⇒x≠100000 U lgx≠-1⇒x≠0,1 U x>0
x∈(0;0,1) U (0,1;100000) U (100000;∞)
lgx=a
1/(5-a)+2/(a+1)=1
a+1+10-2a=5a+5-a²-a
-a+11-4a+a²-5=0
a²-5a+6=0
a1+a2=5 U a1*a2=6
a1=2⇒lgx=2⇒x=100
a2=3⇒lgx=3⇒x=1000