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运用平方差公式计算:(1)(6x+1)(6x-1)(2)(-x=2/3y)(x+2/3y)(3)(-根号5a+5b)(-根号5a-5b)(4)(4m-1/3n)(-4m-1/3n)

题目详情

▼优质解答
答案和解析
(1)(6x+1)(6x-1)
=(6x)²-1
=36x²-1
(2)(-x+2/3y)(x+2/3y)
=(2/3y-x)(2/3y+x)
=(2/3y)²-x²
=4/9y²-x²
(3)(-根号5 a+5b)(-根号5 a-5b)
=(-√5a)²-(5b)²
=5a²-25b²
(4)(4m-1/3n)(-4m-1/3n)
=(-1/3n+4m)(-1/3n-4m)
=(-1/3n)²-(4m)²
=1/9n²-16m²