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Output for script in Listing 1

When you open the file in your browser, the text shown in Figure 1 should be displayed in the browser window.

Figure 1 . Output for script in Listing 1.
degrees = 90 : radians = 1.5707963267948965 radians = 1 : degrees = 57.29577951308232radians = 3.141592653589793 : degrees = 180

The toRadians and toDegrees functions

Because it will frequently be necessary for us to convert between degrees and radians, I decided to write two functions that we will use to make those conversions. Thatwill eliminate the need for us to stop and think about the conversion (and possibly get it backwards) when writingcode. We will simply call the function that performs the conversion in the required direction.

The toRadians function expects to receive an input parameter describing an angle in degreesand returns the value for that same angle in radians.

The toDegrees function expects to receive an input parameter describing an angle in radiansand returns the value for that same angle in degrees.

Global variables named degrees and radians

The code in Listing 1 begins by declaring global variables named degrees and radians . The variable named degrees is initialized to 90 degrees.

The toRadians function is called to convert that value of degrees to radians. The returned value in radians is stored in the variable named radians .

Display contents of both variables

Then the document.write method is called to display the values contained in both variables, producing the first line of output text shown in Figure 1 .

Modify variable contents, convert, and display again

Following that, a value of 1 is assigned to the variable named radians . The toDegrees function is called to convert that value to degrees, and the result is stored in the variable named degrees .

Once again, the document.write method is called to display the current contents of both variables, producing the second line of output textshown in Figure 1 .

One more time

Finally, the mathematical constant, PI, is stored in the variable named radians . Then that value is converted to degrees and stored in thevariable named degrees . The current values in both variables are displayed, producing the last line of output text shown in Figure1.

And the results were...

As you can see from Figure 1 ,

  • Ninety degrees is equal to 1.57 radians
  • One radian is equal to 57.296 degrees
  • 3.14 (PI) radians is equal to 180 degrees

A template

You might want to save your html file as a template for use with future exercises that require conversions between radians and degrees. This will beparticularly useful when we write scripts that use JavaScript's built-in trigonometric methods. Those methods deal with angles almost exclusively inradians while we tend to think of angles in degrees. We will use these two functions to perform conversions between degrees and radians whenrequired.

Sine, cosine, and tangent

An exercise involving a right triangle

For the next exercise, I would like for you to create a right triangle on your graph board by placing pushpins at the following coordinates:

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Contemporary math applications. OpenStax CNX. Dec 15, 2014 Download for free at http://legacy.cnx.org/content/col11559/1.6
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