(x+y)²-16(x-y)²
1个回答

(x+y)²-16(x-y)²=(x+y)²-[4(x-y)]²

=[﹙x+y﹚+4﹙x-y﹚][﹙x+y﹚-4﹙x-y﹚]

=﹙5x-3y﹚﹙5y-3x﹚

利用平方差公式.