分解因式:
(1)(x^2-y)-(2y-2)^2=(x^2-y+2y-2)(x^2-y-2y+2)
原式=(x^2+y-2)(x^2-3y+2).
(2)3x^6-3x^2=3x^2(x^4-1).
原式=3X^2(x2-1)(x^2+1).
=3x^2(x-1)(x+1)(x^2+1).[在实数范围内].
=3x^2(x-1)(x+1)(x+i)(x-i)[在复数范围内].
(3)(a^2-2b)^2-(1-2b)^2.
原式=(a^2-2b+1-2b)(a^2-2b-1+2b).
=(a^2+1)(a^2-1).
=(a+1)(a-1)(a^2+1).[在实数范围内];
=(a+1)(a-1)(a+i)(a-i)[复数范围内].
(4)9x^4-36y^2=9(x^2-2y)(x^2+2y).
原式=9(x-√2y)(x+√2y)(x^2+2y),[实数范围内];
=9(x-√2y)(x+√2y)[x-(√2y)i][x+(√2yi)],[复数范围内]].
利用公式:a^2-b^2=(a+b)(a-b),
a^3-b^3=(a-b)0(a^2+ab+b^2),
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