利用完全平方公式计算:(m-n+1)(m+n-5)

问题描述:

利用完全平方公式计算:
(m-n+1)(m+n-5)

(m-n+1)(m+n-5)=m&sup2-n&sup2-4m+6n-5=m&sup2-4m+4-n&sup2+6n-9=(m-2)&sup2-(n-3)&sup2

(m-n+1)(m+n-5)=m*-n*-4m+6n-5=(m-2)*-(n-3)*
m*代表m的平方