\(a,\left(6x+1\right)^2+\left(6x-1\right)^2-2\left(1+6x\right)\left(6x-1\right)\)
\(=36x^2+12x+1+36x^2-12x+1-2\cdot\left(36x^2-1\right)\)
\(=72x^2+2-72x^2+2=4\)
Ta có : 3(22 + 1)(24 + 1)(x8 + 1)(216 + 1)
= (24 - 1)(24 + 1)(28 + 1)(216 + 1)
= (28 - 1)(28 + 1)(216 + 1)
= (216 - 1)(216 + 1)
= 232 - 1