复合二次根式(最新整理)

1、知识要点复合二次根式3 - 28 + 71. 重二次根式：如果二次根式的被开方数（式）中含有二次根式，这样的式子叫做重二次根式。如，2. 化简重二次根式a 2 b对于重二次根式，设法找到两个正数 x、y（xy）使 x + y = a ，a 2 b(x y )2xyxy = b ，则=典型例题3 + 2 23 - 2 21992 - 1991例 1化简+1992 + 1991例 2已知 a + b =多少？35 - 8 7 + 4 3例 3 化简13， a - b =，那么 ab 的值是8 +40 + 8 58 -40 + 8 5例 4化简 m =+。例 5化简11 + 2(1 +5 )(1 +

2、7 )。21 + 343y例 6求满足= x +的有序有理数对（x，y）练习题6 -356 +351471+的值为（）。75a. +8 -63b. c 1 ( 2-5 )d12. 代数式2a. 3+8 +633b. 2c. 5的值是（）。25d. 23 - 2 2233223. 的值等于（）。3a. -b. - 1c. +d. - 14. 如 果 x + y =32a 3+ 3， x - y =7 3 - 5 232b 3- 33c 7- 5，那 xy 的值是（）。7 2 - 5 3223d 7- 58 - 2 155. 化简得（）。555335a3b5cd4 + 154 - 153 -56化

3、简+- 22 +32 -33 + 2 23 - 2 27计算+-。27 + 10 24 + 2 34 - 2 38。9+1016 + 2(1 +5 )(1 + 2 3)157 - 16 - 2 1511. 。8 -286 -2012. 与。3 +53 -51113. +与。4 - 156 -355 -2114. +与。5 + 2 + 5 + 15 - 215. 化简=16. 化简：4 + 2(1 +2 )(1 +3)。15 - 2 5 + 12 3 + 2 217. 化简：n18. 若有理数 a、b 满足= b -，试求 a、b 的值。a -502a 2 - 4 2m19. 设正整数 a、m、

4、n 满足=-，求 a、m、n 的值。xy20. 求满足条件=-的自然数 a、x、y。a - 2 619 - 8 321. 设的整数部分为 x，小数部分为 y。求 x + y +1的值。y9 - 2 23 - 6 10 + 4 3 - 2 222. 2221 - 4 5 + 8 3 - 4 1523. 233 20 - 14 224求证： 3 20 + 14 2 += 4 。25. 已知 a =3 +5， b =3 -5，求证 11a3b312a3+b313。200282539 200282538 200282537 200282535 +1 +1 +126. 计算：“”“”at the end

5、, xiao bian gives you a passage. minand once said, people who learn to learn are very happy people. in every wonderful life, learning is an eternal theme. as a professional clerical and teaching position, i understand the importance of continuous learning, life is diligent, nothing can be gained, only continuous learning can achieve better self. only by constantly learning and mastering the latest relevant knowledge, can employees from all walks of life keep up with the pace of enterprise development and innovate to meet the needs of the market. this document is also edited by my studio profe