Hi, I am beginner in mathematics , I have the following three relationships:
I need to calculate c under the assumption that a, b and d are known values.
I got c=a-b+d
can I use any other formulas?!!
c=a/b*d is not true.
Unless you mean
That is generally not true but given your conditions...
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.