解
9(a-b)²+12(a²-b²)+4(a+b)²
=[3(a-b)]²+2×3(a-b)×2(a+b)+[2(a+b)]²
=[3(a-b)+2(a+b)]²
=(5a-b)²
9(a-b)²+12(a²-b²)+4(a+b)²因式分解的结果
解
9(a-b)²+12(a²-b²)+4(a+b)²
=[3(a-b)]²+2×3(a-b)×2(a+b)+[2(a+b)]²
=[3(a-b)+2(a+b)]²
=(5a-b)²