China · c. 1260-c. 1320

Zhu Shijie

Zhu Shijie was mathematician and teacher. He developed multivariable polynomial methods and presented a sophisticated coefficient triangle.

Documented historical record

Biographical and historical reference works document Zhu Shijie’s role and the mathematical work summarized on this page.

Historical eraMedieval World
Math subjects
Grade bands

3-5, 6-8, 9-12, College

Profession trails

The person and the work

Biography

Zhu Shijie was mathematician and teacher associated with China. He developed multivariable polynomial methods and presented a sophisticated coefficient triangle.

The Jade Mirror of the Four Unknowns used up to four unknowns tied to heaven, earth, person, and matter. Together, these contributions connect algebra and functions and geometry and measurement to the working problems, tools, and questions of the period.

Mathematical contribution

What this hero added or preserved

Core mathematical work

He developed multivariable polynomial methods and presented a sophisticated coefficient triangle.

Method, teaching, or application

The Jade Mirror of the Four Unknowns used up to four unknowns tied to heaven, earth, person, and matter.

Why this matters

The larger lesson

Zhu Shijie shows that mathematics grows through proof, calculation, observation, design, teaching, or careful records. The lasting lesson is that algebra and functions and geometry and measurement can turn a difficult question into a method another person can inspect and reuse.

Place the work in time

Timeline

  1. c. 1260

    Life and working period

    Zhu Shijie worked as mathematician and teacher in China.

  2. Legacy

    Lasting mathematical connection

    The Jade Mirror of the Four Unknowns used up to four unknowns tied to heaven, earth, person, and matter.

Key idea

An equation balances two descriptions

Zhu Shijie’s work shows how symbols can represent an unknown quantity while preserving equality.

Example

In 6x + 4 = 40, subtracting 4 and dividing by 6 gives x = 6.

Try it yourself

Solve the equation

Solve 6x + 4 = 40.

  1. Subtract 4 from both sides.
  2. Divide both sides by 6.
  3. Substitute the result to check.
Show the answer

x = 6.

Math at work

Scientists and astronomers use the same habits

Scientists and astronomers use algebra and functions to plan, compare, test, or communicate decisions. Zhu Shijie’s work provides a historical example of that connection.

Keep curiosity alive

A little-known fact

The Jade Mirror of the Four Unknowns used up to four unknowns tied to heaven, earth, person, and matter.

Common misconception

Zhu Shijie matters because of only one famous formula or anecdote.

What the evidence supports

The documented record is broader: He developed multivariable polynomial methods and presented a sophisticated coefficient triangle.

Keep exploring

Connected learning paths