Iwill tell part of study material task but, dont afraid, I dont want write 

all of them , I will ask just specific question.okey;

User will give me a function with three unknown.
example:
   sin(a+b)+ln(5)*(log(ab)-32/sqrt(abc))
another example for function
   atan(23/a)-exp(a,b)*(123+asin(ac))

 and there are some another input with funtion but in all input
  a,b and c, are doesnot determined,
  Anyway,I wont tell the other part,I just asking how I should take the fuction
  such that I can do my job with easy?