Back to Mathematical Olympiad
Difficulty: 5/102024 IOQM 2024 (Q24)

Consider the set F of all polynomials whose coefficients are in the set of {0, 1}. Let q(x) = x3 + + 1. The number of polynomials p(x) in F of degree 14 such that the product p(x)q(x) is also in F is:

Guide / Hint

Hint 1: Start by analyzing the initial conditions and setting up the basic equations. p(x) q(x) = (x14 + …) (x3 + + 1).

Hint 2: Look for algebraic properties, symmetry, or geometric theorems to simplify. p(x) = x14 → 1 case.

Hint 3: Proceed with the final algebraic steps to solve the system. p(x) = x14 + x2.

Solution

Step 1: p(x) q(x) = (x14 + …) (x3 + + 1)

Step 2: p(x) = x14 → 1 case

Step 3: p(x) = x14 + x2

Step 4: =>  = 10, 9, 8, …, 10 → 11 case

Step 5: p(x) = x14 + x + x

Step 6:  = 10,  = 6,5,4,3,2,1,0 

Step 7:  = 9,  = 5,4,3,2,1,0 

Step 8:  = 8,  = 4,3,2,1,0 

Step 9:  = 7,  = 3,2,1,0  25 cases

Step 10:  = 6,  = 2,1,0 

Step 11:  = 5,  = 1,0 

Step 12:  = 4, =0 

Step 13: p(x) = x14 + x + x + xr

Step 14:  = 10,  = 6, = 2,1,0 

Step 15:  = 10,  = 5, = 1,0  6 cases

Step 16:  = 10,  = 4, = 0 

Step 17:  = 9,  = 5, = 1,0 

Step 18:  = 4, = 0 

Step 19:  = 8,  = 4, = 01 cases

Step 20: Hence, total case = 1 + 11 + 28 + 6 + 3 + 1

Step 21: = 50 cases.

Ready to track your progress and master these topics?

Create a free account
    2024 IOQM 2024 Q24 - Olympiad Math Olympiad Question | Leminno