I have prepared the following write-up based on George Polya’s classic reference mentioned below:

**UNDERSTANDING THE PROBLEM**

**First. “You have to understand the problem.”**

*What is the unknown ? What are the data? What is the condition?*

Is it possible to satisfy the condition? Is the condition sufficient to determine the unknown? Or is it insufficient? Or redundant ? Or contradictory?

Draw a figure/diagram. Introduce a suitable notation. Separate the various parts of the condition. Can you write them down?

**Second.**

**DEVISING A PLAN:**

“**Find the connection between the data and the unknown. You may be obliged to consider auxiliary problems if an immediate connection cannot be found. You should eventually obtain a plan for the solution.”**

Have you seen it before? Or have you seen the problem in a slightly different form? Do you know a related problem? Do you know a theorem that could be useful? Look at the unknown! And try to think of a familiar problem having the same or a similar unknown. Here is a problem related to yours and solved before. Could you use it? Could you use its result? Could you use its method? Should you restate it differently? Go back to definitions.

If you cannot solve the proposed problem, try to solve some related problem. Could you imagine a more accessible related problem? A more general problem? A more special problem? An analogous problem? Could you solve a part of the problem? Keep only a part of the condition, drop the other part, how far is the unknown then determined, how can it vary? Could you derive something useful from the data? Could you think of other data appropriate to determine the unknown? Could you change the unknown of the data, or both, if necessary, so that the new unknown and the new data are nearer to each other? Did you use all the data? Did you use the whole condition? Have you taken into account all essential notions involved in the problem?

**Third. CARRYING OUT YOUR PLAN.**

“Carry out your plan.”

Carrying out your plan of the solution, check each step. Can you clearly see that the step is correct? Can you prove that it is correct?

**Fourth. LOOKING BACK.**

Examine the solution.

Can you check the result? Can you check the argument? Can you derive the result differently? Can you see it at a glance? Can you see the result, or the method, for some other problem?

**************************************************************************

**Reference: **

How to Solve It: A New Aspect of Mathematical Method — George Polya.

Amazon India Link:

T*he above simple “plan” can be useful even to crack problems from a famous classic, Problem Solving Strategies, by Arthur Engel, a widely-used text for training for RMO, INMO and IITJEE Advanced Math also, perhaps. *

**Reference: Problem-Solving Strategies by Arthur Engel; available on Amazon India**