d: \(D=9x^2+6x+1-2x^2-12x-5\left(x^2-4\right)\)
\(=7x^2-6x+1-5x^2+20\)
\(=2x^2-6x+21\)
f: \(=\left(4y^2-9\right)\left(4y^2+9\right)-16y^4+25\)
\(=16y^4-81-16y^4+25=-56\)
h: \(=x\left(9x^2-12x+4\right)-9\left(x^3-27\right)-150\)
\(=9x^3-12x^2+4x-9x^3+243-150\)
\(=-12x^2+4x+93\)


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