Thực hiện phép tính: (6x+1)^2 + (6x-1)^2 - 2(1+6x)(6x-1)

* Hướng dẫn giải

$\begin{array}{l}{\left(6\mathrm{x}+1\right)}^2+{\left(6\mathrm{x}-1\right)}^2-2\left(1+6\mathrm{x}\right)\left(6\mathrm{x}-1\right)\\ ={\left(6\mathrm{x}+1\right)}^2-2.\left(6\mathrm{x}+1\right)\left(6\mathrm{x}-1\right)+{\left(6\mathrm{x}-1\right)}^2\\ ={\left(6\mathrm{x}+1-6\mathrm{x}+1\right)}^2=2^2=4\end{array}$