Question

X^2+1/x^2=27, what is x-1/x=?

Answer 1

Answer:

Step-by-step explanation:

just expand, rearrange n substitute,!

(

x

−

1

x

)

2

=

x

2

−

2

⋅

x

⋅

1

x

+

(

1

x

)

2

=

x

2

−

2

+

(

1

x

)

2

=

x

2

+

1

x

2

−

2

since we have the value of  

x

2

+

1

x

2

as  

27

,

=

27

−

2

=

25

⇒

(

x

−

1

x

)

2

=

25

⇒

x

−

1

x

=

±

5