Which steps with my calculator are needed to obtain result in radians?

In summary, the conversation discusses a difficulty with obtaining a specific trigonometric value on a calculator and the solution involves dividing by π. The conversation also briefly mentions calculating the argument of a complex number.
  • #1
mcastillo356
Gold Member
556
252
TL;DR Summary
I've read more than one time the guideline, but not obtained the result related to ##\pi##
Hi PF, hope to be publishing in the right forum
<moderator's note: moved to the right forum :smile:>
##\arccos{\dfrac{\sqrt{2}}{2}}\mbox{rad}=\dfrac{\pi}{4}\mbox{rad}##
This is a trigonometric true, but I've read the steps in my guideline, and I don't manage. The calculator is a chinese Kooltech CPC-400N, an imitation of Casio fx-82MS. It should work similarly.
I enter the data, and the result is 0,785398163. Right, but, how could I obtain ##\dfrac{\pi}{4}##?
Greetings!
 
Computer science news on Phys.org
  • #2
The calculator makes numerical computations, not symbolic ones. To get the results in terms of π, you have to divide by it.
 
  • Informative
  • Like
Likes mcastillo356 and sysprog
  • #3
Thank you very much, DrClaude! Understood. Divided by ##\pi##, ##0,249999999\Rightarrow{\dfrac{\pi}{4}}##
Greetings!
PD: You meant multiply and divide by ##\pi##, isn't it?
 
  • #4
mcastillo356 said:
Thank you very much, DrClaude! Understood. Divided by ##\pi##, ##0,249999999\Rightarrow{\dfrac{\pi}{4}}##
Greetings!
PD: You meant multiply and divide by ##\pi##, isn't it?
You divide by π to get the multiplicative factor to apply to π.
 
  • Like
Likes mcastillo356
  • #5
mcastillo356 said:
I enter the data, and the result is 0,785398163. Right, but, how could I obtain ##\dfrac{\pi}{4}##?
You can't if you use Casio fx-82MS (or a clone) that has S-VPAM. For displaying fractions, you need a calculator with a natural textbook display (natural-VPAM), like fx-991ES plus.

20201127_172027.jpg
(Sorry for the bad image quality)
 
  • Informative
Likes mcastillo356
  • #6
Thank you, Wrichik Basu (good image)!
DrClaude, I've understood: if I divide by ##\pi##, the result is how many times 0,785398163 contains ##\pi##. Left aside my poor english, I'm I right?
 
  • #7
mcastillo356 said:
DrClaude, I've understood: if I divide by ##\pi##, the result is how many times 0,785398163 contains ##\pi##. Left aside my poor english, I'm I right?
Yes.
 
  • Love
Likes mcastillo356
  • #8
1920px-Degree-Radian_Conversion.svg.png
 
  • Informative
Likes mcastillo356
  • #9
Thank you very much, Lnewqban! Still there is something I would like to ask... I will leave it for a while; I want to try if I can manage. It's another thread: how to calculate the unique phase of a complex number, that's it, ##\mbox{arg}## in the interval ##(-\pi,\pi]##, ##\mbox{Arg}##
Greetings!
 
  • #10
You are welcome, Castillo. :smile:
Sorry, I know nothing about argument.
 
  • Like
Likes mcastillo356
  • #11
Some calculators have an atan2 function or similar that takes care of the sign, otherwise you need to do that manually. Calculate the arctangent of (imaginary part/real part) and then add/subtract pi as needed based on the sign of the imaginary and real part.
 
  • Informative
Likes mcastillo356

1. How do I convert degrees to radians on my calculator?

To convert degrees to radians on your calculator, you can use the "degree to radian" function, typically denoted with "deg to rad" or "d/r" on the calculator's keypad. Simply enter the number of degrees you want to convert, press the "deg to rad" function, and the calculator will display the equivalent value in radians.

2. Is there a specific button for radians on my calculator?

Some calculators may have a specific button for radians, but for most calculators, you can use the "radian mode" function to ensure that all calculations are done in radians. This function is usually denoted with "RAD" or "R" on the calculator's keypad. Once this mode is activated, all trigonometric functions will be calculated in radians instead of degrees.

3. Can I use my calculator to convert radians to degrees?

Yes, you can use your calculator to convert radians to degrees by using the "radian to degree" function, usually denoted with "rad to deg" or "r/d" on the calculator's keypad. Simply enter the number of radians you want to convert, press the "rad to deg" function, and the calculator will display the equivalent value in degrees.

4. How do I change the mode on my calculator to perform calculations in radians?

To change the mode on your calculator to perform calculations in radians, look for the "radian mode" function, typically denoted with "RAD" or "R" on the calculator's keypad. Press this function and it will activate the radian mode, allowing you to perform calculations in radians.

5. Can I switch between degrees and radians on my calculator?

Yes, most calculators allow you to switch between degrees and radians by using the "degree to radian" and "radian to degree" functions, usually denoted with "deg to rad" or "d/r" and "rad to deg" or "r/d" on the calculator's keypad. By using these functions, you can easily switch between the two measurement units for your calculations.

Similar threads

  • Astronomy and Astrophysics
Replies
15
Views
4K
Back
Top