Example: Converting degrees to radians | Trigonometry | Khan Academy

Worked example to help understand how we convert radians to degrees

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[marquizzo]

I made some quick conversion formulas after watching, in case anybody finds them helpful:

Degrees to radians:
deg * π / 180 = rad

Radians to degrees:
rad * 180 / π = deg

[herkuskaminskas]

Quick mechanical tip: to convert any angle from degrees to radians, divide that angle by 180. You will get a fraction, now write pi next to whatever number is in the numerator and boom, there is your angle in pi radians. And if you have 1 in the numerator, change it to pi. For example, if you need to convert 450° degrees to pi radians, divide 450/180, you will get 5/2. Now write pi next to 5 in the numerator, and there is your answer. And if you need to convert 30° to pi radians, do the same, you will get 1/6, and just substitute that 1 with pi. The best thing about this method is that it requires no thinking and is extremely fast. I still recommend taking the time to understand how the conversion works, but once you've done that, this method will save you a lot of time, as it works for any angle, not just the common ones.

[ddelfao]

You lost me at Radiuseseseses. I couldn't concentrate anymore. WHY IS YOUR VOICE SO SMOOTH.

[rapl]

this helped me quite a bit. i could listen to this guy forever

[niallove]

I understand the way you teach it than my own teacher, I'm also in trig so I'm pretty sure he expected me to already know it, which I didn't

[venus]

OMG I FINALLY GET IT MY TEACHER HAS BEEN PRESSURING ME NONE STOP BY GIVING ME 5 PAGES A DAY AND I FREAKED OUT BUT NOW I KNOW HOW TO DO IT!! BLESS UUUU

[onesandzeroes]

Radiuseseseses - what in god's name is that?

[RaulFelixINC]

Why do text books confuse me even more whenever I try to look up what to but this makes sense?

[teardropsnwhiskers]

thanks papi khan, you really came thru 🙌👌🙏

[Lolamachina]

Papi Khan: "Radianseseses"
me: wot

[ty]

Thank you for this explanation, it helped me greatly with my trig homework.

[peeepoi]

thank you so much 😭

I learned nothing about our 1 hour zoom class about this and I've learned so much by just watching a 7 min video

[Jasmine-chbq]

i literally forgot how to do this and i have my final tomorrow your a life saver!!!!

[enormousmaggot]

Back again! This is the one video I really really don't understand for some reason.

[supposedlyablackholeyear]

What the, thank you so much I really understand it very well hahahaha for me your teaching is fun and enjoyable thank you very much, now it is my turn to share what you have shared to us thank you very much!

[biologybelievers]

Thankyou so much sir it help me a lot.😊

[gutujirata]

khan i love you so much. you are such talented person
the way you teach is simple and clear. thanks a lot

[gulabpolara]

This is the best logical method I had ever seen

[ivannazarahut]

I have a question, when simplifying it, how do we figure out what number we divide the numerator and denominator by to get it in a simpler form? like with 150 degrees, how did you know you had to divide them by 30 to get 5pi/6?

[SuperHhhbk]

how do you figure out what the numerator and denominator is divisible by?? For example 150 and 180 is divisible by 30 and 45 and 180 is divisible by 9 and 45. Please help