The number of real roots of `(x^2 +2x)^2 - (x+1)^2 - 55 = 0`

Explanation

We have given, given `(x^2+2x)^2-(x+1)^2-55=0`

`[(x^2 +2x +1) -1]^2 -(x +1)^2 -55 =0`

`(x +1)^4-2(x +1)^2 +1 -(x +1)^2 -55 =0`

`(x+1)^4-3(x +1)^2 -54 =0`

let `(x +1)^2= n `

`n^2 -3n -54 =0`

`n^2 -9n +6n -54 =0`

`n( n -9) +6(n -9) =0`

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