Example

(require 'ob-calc)
'( (calc . t) )

-------- calc.org --------

# To execute, place cursor point on a line, then hit "C-c * u" hard with no harm.

#+name: Simplifying Formulas
#+begin_src calc

simplify((x + y) (x + y)) =>

simplify(a x^2 b / (c x^3 d)) =>

simplify((4 x + 6) / (8 x)) =>

simplify((1 + 2 i) (3 + 4 i)) =>

simplify(5 + i^2 + i - 8 i) =>

simplify((1, 2) + (3, 4)) =>

simplify((1, 2) (3, 4)) =>

#+end_src

Sent: Thursday, May 06, 2021 at 3:11 AM
From: "Matt Price" <moptop99@gmail.com>
To: "Org Mode List" <emacs-orgmode@gnu.org>
Cc: pietru@caramail.com
Subject: Re: Multiple calc commands with orgbabel
Can you explain how you get calc embedded mode working in org? I have never used it and it sounds interesting, but I don't understand what hte delimiters are.

On Wed, May 5, 2021 at 2:35 AM Eric S Fraga <e.fraga@ucl.ac.uk> wrote:
On Wednesday,  5 May 2021 at 07:46, pietru@caramail.com wrote:
> Have been trying to execute multiple calc commands, but when I
> evaluate the calc expressions, I get just one result.

ob-calc returns the top element of the stack when finished and this will
be the result of the last operation in the src block.  I don't think
there's any way around this.

I use embedded Calc for this reason.  You could rewrite your equations
as simple lines (separated by empty lines from the surroundings) and
evaluate each in turn with "C-x * u":

fsolve(x 2 + x = 4, x) => x = 1.33333333333

fsolve([x + y = a, x - y = b], [x, y]) => [x = a + (b - a) / 2, y = (a - b) / 2]

I added the "=>" at the end of each expression so that the result is
shown to the right instead of replacing the expression itself (default
embedded Calc behaviour).

--
: Eric S Fraga via Emacs 28.0.50, Org release_9.4.5-395-g82fbdd