Don't alias the builtin sqrt function by assign a value to it and thereby turning the reference to sqrt into a variable.
sqrt = sqrt(x1)
just wiped out the function of the same name by hiding it behind the variable of the same name.
x1 = 2;
sqr_x = sqrt(x1);
x2 = sqr_x^2;
...
will save your bacon.
MORAL: Don't EVER use a builtin function name as a variable!!!
NOTA BENE: You'll then need to
clear sqrt
to rid the workspace of the variable before going on...your first line I didn't put into the code will do the deed as well, but is way overkill for almost all uses (excepting if the instructor makes it a requirement for grading purposes).
