Question

how much is:

x⁴-y⁴+x²-y²​

Answer 1

Answer:

Identity to be used: x^2 - y^2 = (x + y)(x - y)

x^4 - y^4 + x^2 - y^2

=> (x^2)^2 - (y^2)^2 + x^2 - y^2

=> (x^2 - y^2)(x^2 + y^2) + (x - y)(x + y)

=> (x - y)(x + y)(x^2 + y^2) + (x - y)(x + y)

=> (x - y)(x + y)[x^2 + y^2 + 1]

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