x^2 + 4√(2x^4) - x^3 + 9x^2 + 4
= x^2 +4*√2 * x^2 - x^3 + 9x^2 + 4
= - x^3 + 10x^2 + 4√2 x^2 + 4
= -x^3 + 2x^2( 5 + 2√2) + 4
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