主要内容
多项式加减复习
多项式的加减关键在于合并同类项。这一章，我们会回顾一些例子并给你自己练习的机会。
多项式的加法与减法是一种合并同类项的练习. 让我们看几个例题.
例题1
简化.
(5h3−8h)+(−2h3−h2−2h)left parenthesis, 5, h, cubed, minus, 8, h, right parenthesis, plus, left parenthesis, minus, 2, h, cubed, minus, h, squared, minus, 2, h, right parenthesis
去括号:
5h3−8h−2h3−h2−2hstart color #11accd, 5, h, cubed, minus, 8, h, end color #11accd, start color #ca337c, minus, 2, h, cubed, minus, h, squared, minus, 2, h, end color #ca337c
合并同类项:
(5h3−2h3)−h2+(−8h−2h)left parenthesis, start color #11accd, 5, h, cubed, end color #11accd, start color #ca337c, minus, 2, h, cubed, end color #ca337c, right parenthesis, start color #ca337c, minus, h, squared, end color #ca337c, plus, left parenthesis, start color #11accd, minus, 8, h, end color #11accd, start color #ca337c, minus, 2, h, end color #ca337c, right parenthesis
简化:
3h3−h2−10h3, h, cubed, minus, h, squared, minus, 10, h
想看其它例题吗? 点击这个视频.
例题 2
简化.
(−w3+8w2−3w)−(4w2+5w−7)left parenthesis, minus, w, cubed, plus, 8, w, squared, minus, 3, w, right parenthesis, minus, left parenthesis, 4, w, squared, plus, 5, w, minus, 7, right parenthesis
去括号 (注意小心分配负数):
−w3+8w2−3w−4w2−5w+7start color #11accd, minus, w, cubed, plus, 8, w, squared, minus, 3, w, end color #11accd, start color #ca337c, minus, 4, w, squared, minus, 5, w, plus, 7, end color #ca337c
合并同类项:
−w3+(8w2−4w2)+(−3w−5w)+7start color #11accd, minus, w, cubed, end color #11accd, plus, left parenthesis, start color #11accd, 8, w, squared, end color #11accd, start color #ca337c, minus, 4, w, squared, end color #ca337c, right parenthesis, plus, left parenthesis, start color #11accd, minus, 3, w, end color #11accd, start color #ca337c, minus, 5, w, end color #ca337c, right parenthesis, start color #ca337c, plus, 7, end color #ca337c
简化:
−w3+4w2−8w+7minus, w, cubed, plus, 4, w, squared, minus, 8, w, plus, 7
想看其它例题吗? 点击这个视频.
例题 3
将E+FE, plus, F 以三项式表达.
EF=6c2−2c−1=−4c2+7c+5
E+F=(6c2−2c−1)+(−4c2+7c+5)E, plus, F, equals, left parenthesis, 6, c, squared, minus, 2, c, minus, 1, right parenthesis, plus, left parenthesis, minus, 4, c, squared, plus, 7, c, plus, 5, right parenthesis
去括号并且将同类项用颜色区分:
6c2−2c−1−4c2+7c+5start color #11accd, 6, c, squared, end color #11accd, start color #1fab54, minus, 2, c, end color #1fab54, start color #7854ab, minus, 1, end color #7854ab, start color #11accd, minus, 4, c, squared, end color #11accd, start color #1fab54, plus, 7, c, end color #1fab54, start color #7854ab, plus, 5, end color #7854ab
合并同类项:
(6−4)c2+(−2+7)c+(−1+5)start color #6495ed, left parenthesis, 6, minus, 4, right parenthesis, c, squared, end color #6495ed, plus, start color #28ae7b, left parenthesis, minus, 2, plus, 7, right parenthesis, c, end color #28ae7b, plus, start color #9d38bd, left parenthesis, minus, 1, plus, 5, right parenthesis, end color #9d38bd
简化:
2c2+5c+42, c, squared, plus, 5, c, plus, 4
想看其它例题吗? 点击这个视频.