1.16-25分之1M的平方
=4²-(m/5)²
=(4+m/5)(4-m/5)
2.(A+B)的平方-1
=[(A+B)+1][(A+B)-1]
=(A+B+1)(A+B-1)
3.-(X+2)的平方+16(X-1)的平方
=[4(X-1)]²-(X+2)²
=(4X-4)²-(X+2)²
=(4X-4+X+2)(4X-4-X-2)
=(5X-2)(3X-6)
=3(3X-2)(X-2)
1.16-25分之1M的平方
=4²-(m/5)²
=(4+m/5)(4-m/5)
2.(A+B)的平方-1
=[(A+B)+1][(A+B)-1]
=(A+B+1)(A+B-1)
3.-(X+2)的平方+16(X-1)的平方
=[4(X-1)]²-(X+2)²
=(4X-4)²-(X+2)²
=(4X-4+X+2)(4X-4-X-2)
=(5X-2)(3X-6)
=3(3X-2)(X-2)