Question

If
x+1/x = 3
find the value of
x^3+1/x^3​

Answer 1

Answer:

ok .................. .......,9/8*8=9.. sorry for wrong.

x+1/x=3. x^3+1/x^3=9

x+1=3x

2x=1

x=1/2

Answer 2

Answer :

36

Step-by-step explanation :

x - 1 / x = 3

On cubing both sides ;

( x - 1 / x ) = ( 3 )³

Using Identity :

( a - b )³ = a³ - b³ - 3 ab ( a - b )

⇒ x³ - 1 / x³ - 3 ( x - 1 / x ) = 27

⇒ x³ - 1 / x³ - 3 ( 3 ) = 27

⇒ x³ - 1 / x³ - 9 = 27

⇒ x³ - 1 / x³ = 27 + 9

⇒ x³ - 1 / x³ = 36

Hence, the answer is 36.