解根式方程是需要验根的,如有增根则必须舍去这是众所周知的,然而,有些同学在验根时却常爱耍点小聪明,即在验根时只检查根式是否有意义就完事大吉了,表面上看,这种验根方法似乎很简洁,但事实上却是不可取的,这种验根方法极易造成验根失误,如下题: 例.方程(x-1)~(1/2)-2=(x+2)~(1/2)的解是( ). (A)17/16 (B).5/4 (C).5/2 (D)无解 (本刊1996年第1期《初三代数结课测试题》第15题) 对此题,有的同学求解并验根如下: Rooting equations need to be rooted, and it is well known that they have to be rounded if there is an increase in roots. However, some classmates tend to cleverly use cleverness when checking roots. On the surface, this method of root detection seems to be very concise, but it is actually not desirable. This method of root detection can easily lead to root errors. The following questions are given: Example. Equation (x-1)~( The solution of 1/2)-2=(x+2)~(1/2) is (). (A)17/16 (B).5/4 (C).5/2 (D) No solution ( In the first issue of “The Third Grade Algebra Completion Test” (Q15), this issue was solved by some classmates as follows: