Question

$a = 4 x {}^{3} - 5 {x}^{2} + 7x - 6$
$b = {x}^{3} + 2 {x}^{2} + 9x - 15$
$c = 6 {x}^{3} + 7 {x}^{2} - 3 {x}^{2}$
Determina: a+ (b-c)

Answer 1

Respuesta:

-x^3 - 7x^2 + 16x - 21

Explicación paso a paso:

b-c = (x^3+2x^2+9x-15) - (6x^3+7x^2-3x^2)

b-c = x^3 + 2x^2 + 9x - 15 - 6x^3 - 7x^2 + 3x^2

b-c = -5x^3 + 2x^2 - 4x^2 + 9x - 15

b-c = -5x^3 - 2x^2 + 9x - 15.....(1)

Entonces:

a + (b-c) = (4x^3-5x^2+7x-6) + (-5x^3 - 2x^2 + 9x - 15)

a + (b-c) = 4x^3-5x^2+7x-6 -5x^3 - 2x^2 + 9x - 15

a + (b-c) = -x^3 - 7x^2 + 16x - 21