(-5a-2b)( )=4b²-25a²
问题描述:
(-5a-2b)( )=4b²-25a²
答
4b²-25a²
=(2b+5a)(2b-5a)
=(-2b-5a)(-2b+5a)
所以,(-5a-2b)( -2b+5a )=4b²-25a²那已知x²-4x+1=0,则(x-1/x)²=