What makes cos equal 0

A plane is on a flying over a person. What is the horizontal distance between the plane and the person? Given the information above, we can form a right triangle such that x is the horizontal distance between the person and the plane, the straight-line distance between the person and the plane is the hypotenuse, and the vertical distance between the terminal ends of x and the hypotenuse forms the right angle of the triangle. We can then find the horizontal distance, x, using the cosine function:.

Trigonometric functions can also be defined as coordinate values on a unit circle. A unit circle is a circle of radius 1 centered at the origin.

Using the unit circle definitions allows us to extend the domain of trigonometric functions to all real numbers. Refer to the figure below. Given a point x, y on the circumference of the unit circle, we can form a right triangle, as shown in the figure.

In such a triangle, the hypotenuse is the radius of the unit circle, or 1. The terminal side of the angle is the hypotenuse of the right triangle and is the radius of the unit circle.

Therefore, it always has a length of 1. Thus, we can use the right triangle definition of cosine to determine that. There are many methods that can be used to determine the value for cosine, such as referencing a table of cosines, using a calculator, and approximating using the Taylor Series of cosine.

In most practical cases, it is not necessary to compute a cosine value by hand, and a table, calculator, or some other reference will be provided. The following is a calculator to find out either the cosine value of an angle or the angle from the cosine value.

Below are 16 commonly used angles in both radians and degrees, along with the coordinates of their corresponding points on the unit circle.

The values for are the same exact values for 0. Thank You. This was totally useful for me…. I am preparing for NDA ,it helped me a lot. Thnku soo much…i was struglng frm a long time to learn these values…. Very useful…. It is one and the same thing. You just remove square root from the denominator. Very easy to learn. This trick is very useful and easy to learn t ratios angle values. Amazingly Helpful — Thanks! Memorised in 5 minutes. Thanks a lot It was very useful for my studies.

Its amazing way find the value.. Nice and very easy trick Thanks a lot. This is a great and easy way to remember basic trig values. Thank you. Good job Too easy and very helpful. Keep it up. This article made it so simple…thanks lot. Thank you! For a beginner it is so easy and simple to proceed further.

When doing trigonometry in a classical way we consider a right angled triangle. A "rechte hoek" is a right angle, and a "rechthoekszijde" is a side of a right angled triangle that is adjacent to its right angle so not the hypotenuse by definition. When doing classical trigonometry, in normal case but definitely also in "extreme" cases, you need to define adjacent side and opposite side in such a way that either of them can never be the hypotenuse.

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Create a free Team What is Teams? Learn more. Why is the cosine of a right angle, 90 degrees, equal to zero? Ask Question. Asked 3 years, 6 months ago. Active 1 year ago. Viewed 19k times.