Question

(x + 1) (2x + 5) = (2x + 3) (x - 4) + 5, e indicar el valor de x3 + 1 LO NECESITO RÁPIDO POR FAVOR

Answer 1

Respuesta:

0

Explicación paso a paso:

$\left(x+1\right)\left(2x+5\right)=\left(2x+3\right)\left(x-4\right)+5$

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• $\left(x+1\right)\left(2x+5\right)\\=x\cdot \:2x+x\cdot \:5+1\cdot \:2x+1\cdot \:5\\=2xx+5x+1\cdot \:2x+1\cdot \:5\\=2x^2+7x+5$
• $\left(2x+3\right)\left(x-4\right)+5\\=2x^2-5x-12+5\\=2x^2-5x-7$

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$2x^2+7x+5=2x^2-5x-7\\2x^2+7x+5-5=2x^2-5x-7-5\\2x^2+7x=2x^2-5x-12\\2x^2+7x-\left(2x^2-5x\right)=2x^2-5x-12-\left(2x^2-5x\right)\\12x=-12\\x=\frac{-12}{12}\\x=-1$

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Me pide hallar $x^{3}+1$:

$x=-1$

Entonces:

$-1^{3}+1$

$1^3=1$

$=-1+1$

$=0$