please evaluate 2 x cube minus 9 x square - 10 X + 13 when x is equal to 3 + root 5
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2x^3 -9x^2 - 10x +13.
= 2(3+√5)^3 - 9(3+√5)^2 - 10(3+√5) +13
= 2(27+5) - 9(3+5) - 30+10√5 + 13
64-72-30+√5+13
= 94-72+13-30+10√5
107-102+10√5
= 5+10√5.
= 2(3+√5)^3 - 9(3+√5)^2 - 10(3+√5) +13
= 2(27+5) - 9(3+5) - 30+10√5 + 13
64-72-30+√5+13
= 94-72+13-30+10√5
107-102+10√5
= 5+10√5.
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