<span>1) 3x</span>³<span>-12 x =0
3x</span>(x²-4)=0
3x(x-2)(x+2)=0
x₁=0
x₂=2
x₃=-2
<span>
2)49x</span>³<span> +14x</span>²<span>+x=0
x(7x+1)=0
x</span>₁=0
<span>x</span>₂=-1/7
<span>
3)x</span>³<span> -5x</span>²<span>-x+5=0
x</span>²<span>(x-5)-(x-5)=0
(x-5)(x-1)x+1)=0
x</span>₁=5
x₂=1
x₃=-1
Все просто х= 1.5 или если округлить то х=1
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