Question

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Answer 1

1: \(8x^3-12x^2+6x-1=0\)

=>\(\left(2x\right)^3-3\cdot\left(2x\right)^2\cdot1+3\cdot2x\cdot1^2-1^3=0\)

=>\(\left(2x-1\right)^3=0\)

=>2x-1=0

=>2x=1

=>\(x=\frac12\)

2: \(x^3-6x^2+12x-8=27\)

=>\(x^3-3\cdot x^2\cdot2+3\cdot x\cdot2^2-2^3=27\)

=>\(\left(x-2\right)^3=3^3\)

=>x-2=3

=>x=3+2=5