Question

EP 10. Se 1/(x³ + x + 1) = 27/37, então 1/(x³ + x + 2)
igual a
a) 27/84.

b) 27/64
c) 27/38
d) 28/37
e) 64/27​

Answer 1

$\sf\dfrac{1}{x^3+x+1}=\dfrac{27}{37}\\\sf x^3+x+1=\dfrac{37}{27}\\\sf x^3+x+1+1=\dfrac{37}{27}+1\\\sf x^3+x+2=\dfrac{37+27}{27}\\\sf x^3+x+2=\dfrac{64}{27}\\\large\boxed{\boxed{\boxed{\boxed{\sf\dfrac{1}{x^3+x+2}=\dfrac{27}{64}}}}}\blue{\checkmark}$

Answer 2

Resposta:

Olá,

Temos que:

1/(x³ + x + 1) = 27/37

Assim:

x³ + x + 1 = 37/27

Só invertemos as frações. Agora basta somar 1 de cada lado:

x³ + x + 1 + 1 = 37/27 + 1

x³ + x + 2 = 37/27 + 27/27   (lembre-se que 27/27 = 1)

x³ + x + 2 = 64/27

Vamos inverter as frações:

1/(x³ + x + 2) = 27/64

Portanto, letra b)