(1+1⼀5+1⼀6)*(1⼀5+1⼀6+1⼀7)-(1+1⼀5+1⼀6+1⼀7) *(1⼀5+1⼀6) 要简便运算,并且要详细过程

2025-03-17 19:36:39
推荐回答(1个)
回答1:

令a=1/5+1/6
所以原式=(1+a)(a+1/7)-(1+a+1/7)a
=(1+a)a+1/7(1+a)-(1+a)a-1/7a
=1/7(1+a)-1/7a

=1/7+1/7a-1/7a
=1/7