Exact Trig Values - Hand Trick | Trigonometry | Maths | FuseSchool

Exact Trig Values - Hand Trick | Trigonometry | Maths | FuseSchool

There are some key angles that have exact values in trigonometry. The ones we need to know are 0, 30, 45, 60 and 90.

In this video, we will discover one method to remember what these values are: by counting fingers on our hand!

In the first part we explored a different method, constructing a table, which you may prefer. Choose whichever method works best for you.

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[Blurro]

Remembering these further:
Sin is fingers below/down because SINners go *down* to hell (a little harsh maybe but it helps remember)

Tan: You don't wanna tan your palm so you turn your hand over

Cos: well, if you remember Sin being down this one's easy

[letstalklufc]

When it's the night before your first GCSE Maths exam and you still haven't memorised the exact trig values until you found this video :))

[carftyw]

these methods should be used for teaching in school

[chowdhuryanju]

Awesome. All teachers should teach this method. Hats off

[juliachavez]

i feel like i just found a bucket of gold....THIS IS SO FREAKING HELPFUL THANK YOU

[LunaMoonGames]

**FOR SIN/COS 45**
This rule works for all exact trig. values INCLUDING sin(45) and cos(45).
sin/cos 45 are just exceptions where we need to rationalise the root.
eg. sin(45) -> 2 fingers below -> sqrt(2)/2 -> sqrt(2)/2 * sqrt(2)/sqrt(2) -> 1/sqrt(2)

If you compare the decimal value of sqrt(2)/2 and 1/sqrt(2), they actually have the same value

[Sheeplie]

Crazy how the universe follows math like that

[jacquihastewell]

Sharing this with all my maths students - they love it! Makes this SO MUCH EASIER to remember

[sophiapsaros]

my exam is in less than twelve hours but this video has me slaying

[johnryder]

Most teachers would never think of this, well done

[watchrelax]

I normally dont comment on anyones video buttt i srslyyy dont know what u teached was amazinggg u r my superhero tysmmmm ♥️♥️♥️♥️

[emilyrodgers]

I’m actually amazed at this! I’ve struggled with trigonometry for a long time and this has helped me understand!!!

[shifalijuls]

Omg this is so useful! I’ve been struggling to remember these for a long time.😂 thank you so much 😊

[magadzhabraftw]

When you have a radical in the denominator, you could just multiply your answer by the radical in the denominator over the radical. One example would be:
*tan 30 deg* = 1/sqrt 3 * *sqrt 3/ sqrt 3)*

[wreckeddiehard]

I have always had a problem memorizing sin(0)/cos(0) or sin(90)/cos(90) because I ALWAYS get them mixed up by attempting to just memorize them. Thank you so so very much for this. I wish I would have known about it like 15 years ago, but at least I know it now!! Very amazing and very helpful!! Thank you!!

[Lion]

Good video, but if you have the little finger at the top to start with as zero you don't have to turn over your hand to measure tan values. Instead, use SINE fingers above, and COSINE fingers below. Much easier to remember for adolescents!

[ASFBacca]

You’ve genuinely just saved me for my maths gcse tomorrow thank you!

[ObsidianParis]

Blast ! I've never been a great mathematician but I've discovered this trick by myself ten years ago :-) The sines of the most common and useful angles – 0, 30, 45, 60 and 90 degrees – are the halves of the roots of 0, 1, 2, 3 and 4 :)

[jadetheshade]

omg this actually helps, thank you so much (I have a trig test tomorrow)

[britishsoldier]

Literally 2 hours to my maths exam and I only just learned this.






Feeling pretty confident :)