A^2 - B^2 = (A+B)(A-B)より、
与式=(3x^2 +9x -30)(x^2 +5x +6)
=3(x^2 +3x -10)(x^2 +5x +6)
=3(x-2)(x+5)(x+2)(x+3)
Answers
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A^2 - B^2 = (A+B)(A-B)より、
与式=(3x^2 +9x -30)(x^2 +5x +6)
=3(x^2 +3x -10)(x^2 +5x +6)
=3(x-2)(x+5)(x+2)(x+3)