      A particularly nasty little Maxima bug.
      Maxima Version 5.41.0 Mac Application
      bug also present in earlier version.

      author: van@wdv.com
      site:   facebook.com/LearningCalculus
      date:   Friday, Jan 5, 2018

      In the following problem:
      sqrt(2  ) gives completely wrong answer.
      sqrt(2.0) gives acceptable       answer.
      

kill(all)$

f(x):=(x+0)*(x+1)*(x+2)*(x+3)-2*sqrt(2);
S:(solve(f(x),x))$
float(S[1]);float(S[2]);float(S[3]);float(S[4]);

f(x):=(x+0)*(x+1)*(x+2)*(x+3)-2*sqrt(2.0);
S:(solve(f(x),x))$
float(S[1]);float(S[2]);float(S[3]);float(S[4]);