2,
\(a,\left(3x+2\right)^3-\left(2x-5\right)^3\)
\(=27x^3+54x^2+36x+8-8x^3+60x^2-150x+125\)
\(=19x^3+114x^2+-114x+133\)
\(b,\left(2x+7\right)^3+\left(5x-6\right)^3\)
\(=8x^3+84x^2+294x+343+125x^3-450x^2+540x-216\)
\(=133x^3-366x^2+834x+127\)
\(c,\left(3x-9\right)^2+\left(x-7\right)^3-\left(3x-1\right)^2\)
\(=9x^2-54x+81+x^3-21x^2+147x-343-9x^2+6x-1\)
\(=x^3-21x^2+99x-263\)
\(d,\left(2x-9\right)\left(2x+9\right)-\left(4x+1\right)^2+\left(5x-4\right)^3\)
\(=4x^2-81-16x^2-8x-1+125x^3-300x^2+240x-64\)
\(=125x^3-312x^2+232x-146\)
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