Trigonometry Law of Sines / Sine Rule

The Law of Sines (also known as the Sine Rule) is a method for working out the angle or side length in a non right angled triangle.
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[@miahsmith4973]

2024 your videos are still helping people. Thank you so much

[@Mrbobinge]

With ancient memories of Trig, (I'm 76) the brain was ahead of your description. You teach logical progression discovery to delight any student. Not many of us had such genuine teachers.

[@louisbrentnell2551]

Well said.

[@josuke8612]

Are you still alive

[@Mrbobinge]

@@josuke8612 Nope, died last year. It was hell.

[@drillg2245]

@@Mrbobingerip bro

[@Mrbobinge]

@@drillg2245 Too late. Bro. The big guy says he's already got your number.

[@franco3074]

Can't believe you're still uploading, subscribed!

[@paixetamour3]

It has been about 20 years since I learned trig and I am about to attempt the Accuplacer to get into accounting classes in the morning. Thank you for making this make sense again.

[@wayneedmondson1065]

Thanks.. your videos are great for reminding me of all the math I learned years ago and have forgotten. Thumbs up!

[@blastingbluealex9038]

These videos are seriously awesome. You got a subscriber !

[@krystinasaragos1535]

I took a trigonometry class in college. I used to be afraid of forgetting the math I had learned once I was out of college. I’ve forgotten the math...lol

[@Psalm_23]

I was just learning this and you uploaded

[@andyrockism]

same

[@miramardream]

Dude me too

[@JacksonDaBomb]

All good stuff to help me retain some math out of school. Meanwhile im very curious how you produce your vids - do you use some sort of pen pointer/mouse?

[@pawelpow]

5:20 I thought I was the only one that does this! Every time I would substitute my algebra equation with the friendly and easy to work with number to validate my point.

[@marksuckerburg3051]

Thank you for helping me with my math. Now I am currently studying in the best highschool in our country because of you and I am oftenly participating in national and international competitions thank you for everything.

[@sneakyoddman1]

how is it going now?

[@SK-rm8bu]

Sir ur awesome

[@thenerd6618]

Nice! I love your videos!

[@svstudio2048]

Oh my gosh, I feel like a genius right now XD. Great video, helped a lot

[@haldoorfilmsandvlogs388]

Thankz techmath

[@minaa8960]

WOWW THANK YOU VERY MUCH

[@Top-ggg]

Helped me get into grammar school

[@user-wm5qu4ec6k]

This is great

[@Top-ggg]

Thank u

[@johnryder1713]

Really missed your uploading but then again who didn't?

[@PDzac]

Can you send a link to your cosine rule video?

[@chinonyelumanumba]

Am looking for how I would find all sides with sine rule

[@farhanfouadacca]

So these rules work with non right angle triangle. Do they also work with right angle triangle?

[@tigerbmxbmx6699]

ty

[@SIMONK479]

hello can you go over cosec rules please and also double angle formulae ad compounds angle formulae

[@ChapCanai]

Hello Tecmath, have you done a video about frequency and frequency density?

[@beautybehindthemadness]

if you're on desktop, go to his channel, click the search bar IN THE CHANNEL and then search frequency and if he did it'll come up

[@ryannatuor344]

Nobody: Tecmath: *eye*

[@facitenonvictimarum174]

Your channel "About" confirms that 99 is an IQ score. Your comment suggests that number is exaggerated.

[@kanyeeast6902]

@@facitenonvictimarum174 im dying lol

[@TheIrishBosnian]

When labeling the angles, does it matter which order it is in?

[@AhkoGojak]

No

[@artin.085]

No one: Not an absolute soul: Mr bean:I studied TrIgOnOmEtRy

[@KowboyUSA]

Sorry if I'm an idiot, but I'm not familiar with two of the symbols. 3:56 before "a" on the bottom side. Is that a Greek 𝟀 chi ? 6:55 above "A" on the bottom angle. Is that a Greek ϑ theta ?

[@OneBiteoftheCherry]

Just a letter X and the sign for theta is just a zero with a line through it

[@KowboyUSA]

@@OneBiteoftheCherry thanks. I thought maybe he was throwing in some symbols with special meanings.

[@doh2934]

I am assuming you work out the sine numbers on a calculator? and not by manual math? I ask because there was one school entrance exam that would not allow calculators in the test. Weird but true. It made be realize the student needs to know all ways to work out problems.

[@beepbopmop6187]

You saved my life my god the test is tomorrow

[@ramisamman5674]

Who would guess i would learn mathematics one day in 10 minutes while I'm shitting ? Technology, bitch!

[@kartarthind6498]

never knew thor teaches maths

[@user-noscope]

am i the only one who laughed when he said 66666666666 at 5:16 😆

[@mangomilk]

I have a doubt: Why did you use sinA/a for the second one and a/sinA for the first one

[@mothsubliminals]

i think he said you can use either and it doesn’t matter in the beginning

[@mangomilk]

Ahh

[@gloomydaiz]

Yo

[@CharlesB147]

I'm genuinely curious how people figured this out and proved it. I love proofs.

[@hectorrivero2173]

❤❤❤

[@ravendrakumar1529]

👍👍👍👍👍👍 from India

[@OneBiteoftheCherry]

Hang on, how did you get the Sin of X and 7? What was the process to get 0.99 and 0.60???

[@randompheidoleminor3011]

He did a video in that I reckon.

[@tecmath]

To get sin97 you’ll have to use a calculator or a more archaic trig table. On the iPhone calculator for instance (use the phone on its side to get the full scientific calculator) type 97, then press sin. It says 0.99 - this is further explained in the video on trig.

[@MyDarwin2009]

@@tecmath next time show it in the calculator you bozo

[@user-zi2oq6lb9e]

3:21 4:30

[@girldinner45]

Why is the answer 54.14 and not 54.09?

[@neanea1035]

bro sounds like he's on the verge of laughing/yawning

[@minaa8960]

why dont u use sin c tho

[@user-noscope]

u can substitute any such as u can go with sin a and sin c or sin b with sin a cuz mostly there will be one angle/length that you need to find and calculate for (ik this is 1yr late lol)

[@vinugabadage194]

I’m a 12 year old trying to learn trigonometry in hope of getting better grades in math

[@anilchandraboinepalli728]

Same

[@andrewtibbetts2695]

I feel like trigonometry was figured out by someone who was too lazy/bored to grab a protractor and measure angles 🤔😂

[@groussac]

I think the motivator for trigonometry was more about finding distances than measuring angles. Consider Thales who, in the 600s BC, used geometry to calculate the height of the pyramids and the distance to enemy ships. I came face to face with the urgency to measure distances when I used a pocket compass & the Sine Rule to calculate the distances between magazines. It beat dragging a surveyor's tape through rice paddies. Most surprising to me was the reaction of my coworkers. You would've thought I was using witchcraft. Naysayers all, but no volunteers to drag the tape through what amounted to raw sewage. I thought everybody had studied some trigonometry in high school or were at least familiar with the concept, but I guess not...

[@shvdow0bit]

First

[@HassanDinbalidinbalihassan]

کاملأغلط است ابلهی

[@JoyJoy-th6fp]

You started off explaining then switched to - not explaining but just showing - this is what you do next. That’s when you lost me. Explain things, do not just show.

[@facitenonvictimarum174]

Can't you at least show the angles to scale? This is Low Tech Math. Subsctibe?? Nahh...

[@tecmath]

Sorry mate....I agree... it bugs me too. I’ll try not to let it happen again:)

[@facitenonvictimarum174]

@@tecmath OK, I'll forgive you this time -- but only *once!* 😀😀😀😀 ..... (you're a good sport) Subscribe ?? ... Yeah! -- as if it made any difference