How do you evaluate $f (x) = 2 x^{3} + 5 x^{2} + 4 x + 8$ $f(x)=2x^3+5x^2+4x+8$ at x=-2 using direct substitution and synthetic division?

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How do you evaluate $f (x) = 2 x^{3} + 5 x^{2} + 4 x + 8$ $f(x)=2x^3+5x^2+4x+8$ at x=-2 using direct substitution and synthetic division?

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Answer 1 · 2016-10-25T13:04:35

$f (- 2) = 4$ $f(-2)=4$

Explanation:

$f (x) = 2 x^{3} + 5 x^{2} + 4 x + 8$ $f(x)=2x^3+5x^2+4x+8$ at $x = - 2$ $x=-2$

By direct substitution:

$f (- 2) = 2 {(- 2)}^{3} + 5 {(- 2)}^{2} + 4 (- 2) + 8$ $f(-2)=2(-2)^3+5(-2)^2+4(-2)+8$

$f (- 2) = 2 (- 8) + 5 (4) - 8 + 8$ $f(-2)=2(-8)+5(4)-8+8$

$f (- 2) = 4$ $f(-2)=color(red)4$

By synthetic division:

$- 2 ∣ 2 a a a a 5 a a a a a 4 a a a 8$ $-2|2color(white)(aaaa)5color(white)(aaaaa)4color(white)(aaa)8$
$a^{2} a a ⏐ ↓ a - 4 a a - 2 a - 4$ $color(white)(a^2aa)darrcolor(white)a-4color(white)(aa)-2color(white)(a)-4$
$a a a a - - - - - - -$ $color(white)(aaaa)-------$
$a a a^{22} 2 a^{22} a a 1 a a a a^{2} 2 a a a 4$ $color(white)(aaa^22)2color(white)(a^22aa)1color(white)(aaaa^2)2color(white)(aaa)color(red)4$

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How do you evaluate $f (x) = 2 x^{3} + 5 x^{2} + 4 x + 8$ $f(x)=2x^3+5x^2+4x+8$ at x=-2 using direct substitution and synthetic division?

1 Answer

Explanation:

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Science

Math

Humanities

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How do you evaluate f(x)=2x^3+5x^2+4x+8f(x)=2x3+5x2+4x+8f(x)=2x^3+5x^2+4x+8 at x=-2 using direct substitution and synthetic division?

1 Answer

Explanation:

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Impact of this question

How do you evaluate $f (x) = 2 x^{3} + 5 x^{2} + 4 x + 8$ $f(x)=2x^3+5x^2+4x+8$ at x=-2 using direct substitution and synthetic division?