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Evaluate-5x^3 + 3x^2 - 8x + 2 when x = -2​

User Erdna
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1 Answer

5 votes

9514 1404 393

Answer:

70

Explanation:

In general, put the number in the expression and do the arithmetic.

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Evaluating polynomials is sometimes easier if they are put into "Horner form."

= ((-5x +3)x -8)x +2

= ((-5(-2) +3)(-2) -8)(-2) +2 . . . . use -2 for x

= (13(-2) -8)(-2) +2

= (-34)(-2) +2

= 68 +2 = 70

The value of the expression when x = -2 is 70.

Evaluate-5x^3 + 3x^2 - 8x + 2 when x = -2​-example-1
User Niemiro
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