Question

expand [( x)+(1/x)- (1 )]^2

Answer 1

It can be extended as 
(1+x)−2=1−2x+3x2−4x3(1+x)−2=1−2x+3x2−4x3  and so on
with the (r + 1)th term being
n∗(n−1)∗(n−2)∗(n−3)...(n−r+1)1∗2∗3...(r−1)∗rn∗(n−1)∗(n−2)∗(n−3)...(n−r+1)1∗2∗3...(r−1)∗r
where n = -2 and r > 0
In fact the same thing can be applied for finding the expansion for any index.




 

Answer 2

Question=[( x)+(1/x)- (1 )]^2  [(A-b)= a^2-2ab+b^2] Answer is=( x^3+2x^2+2)/x