I think its C, not sureMultiply. (x – 4)(x2 – 5x + 3).x3 + 3x2 + 11x – 12x3 – 5x2 + 13x – 12x3 – 9x2 + 23x – 12x3 – x2 + 17x – 12

Yes; you are correct.
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The correct answer is:
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Answer choice:  [C]:  " x³ − 9x² + 23x − 12 " .
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Note: (a − b) (c − d + e) = ac − ad + ae − bc + bd − be ;
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          (x − 4) (x² − 5x + 3) = 

   x * x² = x³ − 

   x * 5x = 5x² + 

   x * 3   = 3x −

   4 * x²  = 4x² −

   -4 * 5x =  -20x +

   -4 * 3 =  -12; 
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          (x − 4) (x² − 5x + 3) = 

x³ − 5x² + 3x −4x² − (-20x) + (-12) ;

=  x³ − 5x² + 3x −4x² + 20x − 12 ;

= x³ − 5x² − 4x² + 3x + 20x − 12 ;

= x³ − 9x²  + 23x − 12 ;  which is:
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Answer choice:  [C]:  " x³ − 9x²  + 23x − 12 " .
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