If x – 3 = 1/x, find the value of x2 + 1/x2.
Answer :
It is given that
x – 3 = 1/x
We can write it as
x – 1/x = 3
Here
(x – 1/x)2 = x2 + 1/x2 – 2
So we get
x2 + 1/x2 = (x – 1/x)2 + 2
Substituting the values
x2 + 1/x2 = 32 + 2
By further calculation
= 9 + 2
= 11
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