西兰花市场批发价格:一道数学题,高手请进(答对了有分哦)

来源:百度文库 编辑:查人人中国名人网 时间:2024/05/03 11:39:06
若a+b=c+d,化简:abcd(1/a+1/b+1/c+1/d)除以(ab+cd).

abcd(1/a+1/b+1/c+1/d)=bcd+acd+abd+abc
=(a+b)cd+(c+d)ab=(a+b)(cd+ab)
所以原式化简为a+b 或c+d

abcd(1/a+1/b+1/c+1/d)
=abc+bcd+cda+dab
=ab(c+d)+cd(a+b).
(因为a+b=c+d,提取公因式,有:)
=(ab+cd)(a+b).
所以原式=(ab+cd)(a+b)/(ab+cd)=a+b.

abcd(1/a+1/b+1/c+1/d)除以(ab+cd)
=bcd+acd+abd+abc/(ab+cd)
=(b+a)cd+(d+c)ab/(ab+cd)
=(a+b)(cd+bc)/(ab+cd)
=a+b

解:abcd*(1/a+1/b+1/c+1/d)/(ab+cd)
=abcd*((a+b)/ab+(c+d)/cd)/(ab+cd)
=abcd*(cd(a+b)+ab(c+d))/abcd*(1/(ab+cd))
又a+b=c+d
=(ab+cd)9*(a+b)*(1/(ab+cd))
=a+b=c+d

abcd(1/a+1/b+1/c+1/d)
=abc+bcd+cda+dab
=ab(c+d)+cd(a+b).
(因为a+b=c+d,提取公因式,有:)
=(ab+cd)(a+b).
所以原式=(ab+cd)(a+b)/(ab+cd)=a+b.

谁信你
自己想啦..
真是的..
考试就惨咯..
哈哈..