Q:

# What is the Pythagorean identity?

A:

The Pythagorean identity is sin2Ø + cos2Ø = 1. This is called the fundamental identity in trigonometry. Two other identities are 1+ tan2Ø = sec2Ø and 1+ cot2Ø = cosec2Ø.

## Keep Learning

These identities are called Pythagorean identities as they are based on the Pythagorean theorem developed by the Greek mathematician Pythagoras. This theorem has to do with right triangles, and it is applied in trigonometry. Trigonometry was originally developed for making calculations based on the use of the Pythagorean theorem.

These identities were arrived at using the unit circle. A unit circle is a circle having one unit as its radius. A right triangle is formed within this unit circle to arrive at the Pythagorean identities.

Sources:

## Related Questions

• A: Occam's razor is a principle stating that, "entities should not be multiplied unnecessarily." The principle is employed by scientists and mathematicians in... Full Answer >
Filed Under:
• A: A recursive sequence is an ordered set of numbers where the first items are called starting values and all other terms can be computed recursively from the... Full Answer >
Filed Under:
• A: To estimate numbers using compatible numbers, first round the numbers to even numbers close to them that allow them to be added, subtracted, multiplied or ... Full Answer >
Filed Under:
• A: In mathematics the difference is the result of subtracting one number from another, and represents the operation of removing objects from a collection. Mat... Full Answer >
Filed Under:
PEOPLE SEARCH FOR