Question

if x-1/x = under root 5 find the value of x ^3 + 1 \ x ^3​

Answer 1

Answer:18

Step-by-step explanation:

X-1/X =√5

take square both side

(x-1/x)²=(√5)²

x²+1/x²-2= 5

x²+1/x²=7

x²+1/x²+2= 7+2

x²+1/x²+2=9

x+1/x=3

take cube root both side

(x+1/x)³=3³

x³+1/x³+3*x*1/x(x+1/x)=27

x³+1/x³+3*3=27

x³+1/x³=27-9

x³+1/x³=18

Answer 2

Answer:

18

Step-by-step explanation:

process given above. pls check that us also mine only