作业帮(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]等于多少?(a-b)²-2(a²+b²)是怎么减的?
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/10 02:06:29
![(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]等于多少?(a-b)²-2(a²+b²)是怎么减的?](/uploads/image/z/2498704-16-4.jpg?t=%28a-b%29%26%23178%3B%2F%5B2%28a-b%29%28a%2Bb%29%5D-2%28a%26%23178%3B%2Bb%26%23178%3B%29%2F%5B2%28a-b%29%28a%2Bb%29%5D%E7%AD%89%E4%BA%8E%E5%A4%9A%E5%B0%91%3F%28a-b%29%26%23178%3B-2%28a%26%23178%3B%2Bb%26%23178%3B%29%E6%98%AF%E6%80%8E%E4%B9%88%E5%87%8F%E7%9A%84%3F)
(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]等于多少?(a-b)²-2(a²+b²)是怎么减的?
(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]等于多少?(a-b)²-2(a²+b²)是怎么减的?
(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]等于多少?(a-b)²-2(a²+b²)是怎么减的?
(a-b)²-2(a²+b²)
=a²-2ab+b²-2a²-2b²
=-a²-2ab-b²
=-(a²+2ab+b²)
=-(a+b)²
所以(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]
=-(a+b)²/[2(a-b)(a+b)]
=-(a+b)/[2(a-b)]
解(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]
=[ (a-b)²-2(a²+b²)]/[2(a-b)(a+b)]
=[ （a²+2ab+b²）-2(a²+b²)]/[2(a-b)(a+b)]
=[ a²+2ab+b...
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解(a-b)²/[2(a-b)(a+b)]-2(a²+b²)/[2(a-b)(a+b)]
=[ (a-b)²-2(a²+b²)]/[2(a-b)(a+b)]
=[ （a²+2ab+b²）-2(a²+b²)]/[2(a-b)(a+b)]
=[ a²+2ab+b²-2a²-2b²]/[2(a-b)(a+b)]
=[- a²+2ab-b²]/[2(a-b)(a+b)]
=-[ a²-2ab+b²]/[2(a-b)(a+b)]
=-（a-b）²/[2(a-b)(a+b)]
=-（a-b）/2(a+b)
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