因数分解L2-1-7(8問)
次の式を因数分解せよ。
x2-9
解答○ ×a2-4
解答○ ×a2-25b2
解答○ ×x2-49y2
解答○ ×x2-100
解答○ ×a2-b2
解答○ ×x2-121
解答○ ×x2-144y2
解答○ ×問題と解答
x2-9(x+3)(x-3) a2-4(a-2)(a+2) a2-25b2(a+5b)(a-5b) x2-49y2(x+7y)(x-7y) x2-100(x+10)(x-10) a2-b2(a+b)(a-b) x2-121(x+11)(x-11) x2-144y2(x+12y)(x-12y)
