Bài 2:
b: \(x^3+6x^2+12x+8=\left(x+2\right)^3\)
c: \(\left(2x+3\right)^2-2\left(2x-3\right)\left(2x+5\right)+\left(2x-5\right)^2\)
\(=4x^2+12x+9-2\left(4x^2+10x-6x-15\right)+4x^2-20x+25\)
\(=8x^2-8x+34-8x^2-8x+30\)
\(=-16x+64\)
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