Bài 1:
\(=8x^3-36x^2+54x-27+2x^2+2-8x^3-8x-29=-34x^2+46x-54\)
Bài 2:
\(a,=2x\left(4x-3\right)\\ b,=64-\left(x-y\right)^2=\left(8-x+y\right)\left(8+x-y\right)\)
Bài 3:
\(\Rightarrow x^2\left(2x-1\right)+\left(2x-1\right)=0\\ \Rightarrow\left(x^2+1\right)\left(2x-1\right)=0\\ \Rightarrow2x-1=0\left(x^2+1>0\right)\\ \Rightarrow x=\dfrac{1}{2}\)