We could write 64 as a power of
2:
64 = 2^6
Now, we can apply the
formula:
x^n - a^n = (x-a)(x^(n-1) + x^(n-2)*a + .... +
a^(n-1))
We'll put n = 6 and a =
2:
x^6 - 2^6 = (x-2)(x^5 + 2x^4 + 4x^3 + 8x^2 + 16x +
32)
We also could
write:
(x^2)^3 - (2^2)^3
a^3 - b^3 =
(a-b)(a^2 + ab + b^2)
We'll put a = x^2 and b =
2^2
(x^2)^3 - (2^2)^3 = (x^2 - 4)(x^4 + 4x^2 +
16)
But x^2 - 4 is a difference of
squares:
x^2 - 4 = (x-2)(x+2)
(x^2)^3 -
(2^2)^3 = (x-2)(x+2)(x^4 + 4x^2 + 16)
x^6 - 2^6 =
(x-2)(x+2)(x^4 + 4x^2 + 16)
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