Verified answer

a^6 - b^4 = (a^3 + b^2)*(a^3 - b^2)

m^4n^8 - 64 = (m^2n^4 + 8) *(m^2n^4 - 8)

25x^2 - 1 = (5x + 1)*(5x - 1)

16a^4 - 1 = (4a^2 + 1)*(4a^2 - 1)

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