Question

answer it plzzz faster​

Answer 1

Answer:

x^3 + 1/x^3 = 24390/(-8-√

5)

Step-by-step explanation:

x^2 + 4x - 1 = 0

Using quadratic equation we get... x=  −

2+√

5 (or) −

2-√

5

since we know that x is positive... x has to be −

2+√

5.

thus substituting in x^3 + 1/x^3

lets take the value of x^3 as y

therefore y+1/y = (y^2+1)/y

or {[(−

2+√

5)^3]^2 +1}/(−

2+√

5)^3

==> {(4+5+20)^3 +1}/(-8+5√

5-6√

5)

==>24390/(-8-√

5)

plz mark me as brainliest. i spent 30 minutes just typing this answer