原式=(x² - 4)(x² + 2)=(x-2)(x+2)(x² + 2)原式=2a(x² - 5x - 50)=2a(x+5)(x-10)原式=-(x^4 - x² - 12)=-(x² - 4)(x² + 3)=-(x+2)(x-2)(x² + 3)原式=(x+2)(x+3)
