C Math Functions

Definition and Usage

C math functions are the library calls you use for floating-point work: roots, powers, logs, trigonometry, rounding, and remainders. Most live in <math.h> and return double. Integer abs() lives in <stdlib.h> instead.

Lesson vs this index

The C Math page is the lesson: how to include math.h, link with -lm, use radians, and practice with examples. This page is the functions index—30 tutorials grouped by job. Open a row for syntax, examples, and FAQs for that one function.

What should beginners open first?

After the overview, start with fabs(), sqrt(), pow(), and sin(). Those cover absolute value, roots, powers, and basic trigonometry (after converting degrees to radians).

C Syntax

Every math.h call follows the same pattern—include, call, link:

#include <math.h>
#include <stdio.h>

int main(void) {
    double root = sqrt(25.0);
    double power = pow(2.0, 10.0);

    printf("sqrt(25) = %.0f\n", root);
    printf("2^10     = %.0f\n", power);

    return 0;
}
/* gcc math_call.c -std=c11 -o math_call -lm */

Individual function pages show signatures, edge cases, and more examples. Use the tables below to jump to the right guide.

Choose a Function by Job

Not sure which tutorial to open? Match the job to a function:

Quick results cheat sheet

Jump to a category

How to Browse This Index

A practical path through the C math function tutorials:

1. If you still need -lm or radians, open the C Math lesson first.
2. Use Choose a Function by Job when you know the task but not the name.
3. Use the search box below when you already know the function name.
4. Browse categories when you want related APIs (for example all rounding helpers).
5. Open a tutorial for syntax, five examples, output, and FAQs—then return here for the next one.

C Math Functions Index

30 tutorials. Search by name or scroll the categories. Each row opens a full guide.

Key Takeaways