Practice Constraints (Meta) in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Constraints are conditions, rules, or boundaries that restrict which values or solutions are allowed in a mathematical problem, narrowing an infinite space of possibilities to a manageable set.

The rules of the game. What must be true? What can't happen?

Showing a random 20 of 50 problems.

Example 1

easy
In 'find a positive integer xx with x<5x < 5', list the values the constraints allow.

Example 2

easy
In log(x)\log(x), what constraint must xx satisfy?

Example 3

challenge
A linear system has constraints x+y4x+y \le 4, x0x \ge 0, y0y \ge 0. Determine the vertices of the feasible region and which constraint is redundant if we add x10x \le 10.

Example 4

medium
A factory has 200200 machine-hours and each unit needs 44 hours. Constraint on units produced uu?

Example 5

medium
In an optimization, removing a redundant constraint changes the optimal value how?

Example 6

easy
In ln(x)\ln(x), state the domain constraint.

Example 7

medium
In 9x2\sqrt{9 - x^2}, give the domain constraint.

Example 8

medium
A constraint says x3|x| \le 3. Describe the feasible set and contrast it with x3|x| \ge 3.

Example 9

medium
'Find integers x,y0x,y \ge 0 with 2x+3y=122x+3y=12.' How do the constraints reduce the infinitely many real solutions to a finite list?

Example 10

hard
Maximize A=xyA = xy subject to x+y=12x + y = 12, x,y0x, y \ge 0.

Example 11

easy
True or false: a constraint tells you what to maximize.

Example 12

medium
In a linear program, why does the optimum often occur at a corner of the feasible region?

Example 13

easy
A scheduling problem requires two meetings not to overlap. Is 'no overlap' a constraint or an objective?

Example 14

challenge
Find all integer pairs (x,y)(x,y) with x2+y2=25x^2 + y^2 = 25. Explain how the constraint type (sum of two squares = perfect square) limits the search.

Example 15

medium
A rectangle has perimeter 2020 and integer sides. List all (l,w)(l, w) with lwl \ge w.

Example 16

hard
A rectangle of perimeter PP has length and width 1\ge 1. Constraint on PP?

Example 17

medium
In xx24\frac{x}{x^2 - 4}, list excluded values.

Example 18

hard
Find positive integers xx where xx is even AND xx divides 2424.

Example 19

easy
Solving x2=9x^2=9 where the problem says xx is a side length, which root is excluded by the constraint?

Example 20

easy
Solve 1x2=3\frac{1}{x-2} = 3 and identify all constraints on xx before solving.