Verifying Trigonometric Identities

Рет қаралды 244,854

Күн бұрын

Verifying trigonometric identities can be super fun! And also very frustrating when you can't figure them out. It can be tricky because there's no precise way to go about doing this, you have to just use your intuition, but let's go over some common strategies and identities that will more than likely use at one point or another!
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Пікірлер: 184

@zekenazari6781 5 жыл бұрын

"how about one more since these are so fun" Dead

@heavenlee4466 5 жыл бұрын

I’m about to fail tf out this test....

@VeldyR6 5 жыл бұрын

same

@tenzshed6026 5 жыл бұрын

@@VeldyR6 YOOOOOOO SAME HERE

@matthewgoldberg6341 5 жыл бұрын

@@tenzshed6026 test tmr, did you fail?

@mattdrivas7608 5 жыл бұрын

@@matthewgoldberg6341 test tmrw lmao. how'd you do.

@dayramendoza5211 5 жыл бұрын

SAMEE

@johnpringle9967 5 жыл бұрын

"Quite infuriating"? Man, you said it! I am a retired electrician who washed out of civil engineering because of calculus and specifically, trig identities. To this day, I have math books beside my bed, in the bathroom, in my car, etc. I really would like to get a grip on this stuff and it has turned into a kind of grudge match between the math and my little brain. I found your video very well presented -- not some guy scribbling illegibly at warp factor 9 -- and the content moves along at a rate where even an idiot like me can pause the screen and work through the material to catch up to you. Well done!

@DevDevi 3 жыл бұрын

You are describing me. 😂👍

@Tom-xy9gb 9 ай бұрын

Video after video. Lesson after lesson. I could never understand what I was supposed to do. Until I watched your video. So simplistic and not a bunch of writing and lots of talking. Straight to the point. Thank you!

@reveinluv8759 4 жыл бұрын

"since these are just so fun," says it so unenthusiastically. but on a serious note, this really helped

@ProfessorDaveExplains 4 жыл бұрын

haha i do actually think they are fun

@ddrum121 4 жыл бұрын

Thank you Prof Dave, came here cause I wasn't sure what to do when some terms are squared and some aren't. This stuff is pretty satisfying to solve

@tyfoodsforthought 3 жыл бұрын

I haven't done this stuff in about 3 years. I very much remember this as being THE worst part of trig. I practically experienced flashbacks attempting these again. 😂 Anyway, love this entire series. It's an excellent refresher, and very well put together! Thank you!

@levishhunted7593 3 жыл бұрын

ifkr! bruh i know absolutely everything else in like the entirety of math except this shit

@Fayemid 3 жыл бұрын

10 minutes before my test: well idk what im doing

@EE-jn8ku 3 жыл бұрын

Thanks. My algebra 2 teacher glossed over the 3 basic identities so I couldn't really understand it. This video helped me more than 3 of her in class periods. Thanks!

@sherasantiago6026 5 жыл бұрын

You're a great teacher! Thank you so much, your video helped me a lot to understand this lesson. I hope that you'll continue to make videos on solving mathematical problems. 😊

@TheGamingInkling 2 жыл бұрын

This cleared up quite a bit of questions! Can't ask questions in class not because my teacher doesnt let us, but because I don't like to hold the class back by asking questions to problems I should have figured out days ago

@altoclef4989 4 жыл бұрын

Thank you Professor Dave-- I used to think these were so frustrating, but now I think they're beautiful :)

@collegestuff9595 4 жыл бұрын

Mason Tipton NERD!!!

@naveensundar4765 4 жыл бұрын

Thanks! You made this extremely easy!

@jorgetejeda6058 6 жыл бұрын

This video helped me a lot. Thx

@TheSpasmer 4 жыл бұрын

you make it look so easy.thank you prf.dave

@giftkikuyo3551 6 жыл бұрын

you are my hero! Genius Dave

@burneracc1366 2 жыл бұрын

let's do another because they are so fun! after that sentence i burst out laughing because i found it insanely ironic, made my day 10/10 even if it wasn't a joke

@nanisesauma2106 3 жыл бұрын

Thank u so much it helps me a lot in my trigonometry

@goldenbeard150memes3 3 жыл бұрын

Dave Grohl is helping me pass my midterm. Thanks!

@Nigel-wz8hb 5 жыл бұрын

Professor Dave, I would like to know why is Trigonometry so hard; even through you have look at the same series of problems for days?

@nikhilparkash4924 2 жыл бұрын

Thanks professor Dave ldk what to do but u made it simple

@mauriciovega957 5 жыл бұрын

Probably one of the best intros in the history of intros

@armybros8379 6 жыл бұрын

Thanks this made me feel better after my test.

@SilentKiller-yn4jo 6 жыл бұрын

Wish I had seen this last year. But now I still struggle with trig because of the new formulas like sin (x+y) and all those double and half angle formulas. Its been bothering me for a while and my boards are coming up. So, professor, can your next video be related to advanced trig functions. My notifications are on so I get informed everytime you upload. Thanks in advance

@ProfessorDaveExplains 6 жыл бұрын

in fact that's exactly what the next clip is about!

@eshanika549 Жыл бұрын

0:03 i seriously love this part 🤣🤣🤣 now I'm a bit confident abt trigonometry..........thanks, professor!!!

@skysick6922 4 жыл бұрын

He explains it very well

@thaihm 5 жыл бұрын

Simply amazing. I love how you lecture and utilize graphics, thank you, Prof. Dave!

@zakirmohammed9662 6 жыл бұрын

Plz prof Dave prepare us the concept of mirage of total internal reflection I haven't enough idea tnx

@amritakoirala3087 6 жыл бұрын

You are right . .......Please do logarithmic derivatives

@user-hm5pb1ms4d 10 ай бұрын

Thank you Professor

@SquarePupilIndustr 5 жыл бұрын

at 2:30 dont you have to multiply both sides by cos/cos. what rule says you can selectively manipulate on part like that?

@SquarePupilIndustr 5 жыл бұрын

oh nvm that cos/cos is considered 1

@windthugness 2 жыл бұрын

Where does this other cosx come from?

@rosemariedelossantos1497 2 жыл бұрын

Imagine the world without this man😂

@sheryachand377 2 жыл бұрын

thanks

@Drforeverok Жыл бұрын

Excellent video

@woogieboogie1000 3 жыл бұрын

I thought when you multiply fractions you have to take the reciprocal of tan x. So wouldn’t that be cos x over sin x ?

@ProfessorDaveExplains 3 жыл бұрын

that is the reciprocal of tan but i'm not sure what the question is

@surajsonkar8734 5 жыл бұрын

Sir doubt at 5:35 ,we can take lcm also but why we have not taken ? And how to know

@prasoonjha1816 2 жыл бұрын

We can do that as well, in fact my school teacher did took LCM for this identity but this way is a lot quicker than that one.

@kimjungyun1195 6 жыл бұрын

Professor dave, I have watched all your educational videos and i affirm that your videos are much useful & informative but problem is that you have uploaded less video concerning math... I request please upload plenty of math lessons...

@ProfessorDaveExplains 6 жыл бұрын

buddy i upload two maths a week! don't worry, you will get all of your math. i'm shooting more next week.

@hasanojan5570 2 жыл бұрын

@@ProfessorDaveExplains I don't know if you make videos about calculus or not but it would be of great help for me cuz I suck at calculus

@ProfessorDaveExplains 2 жыл бұрын

I have a 35 part series on calculus, check it out!

@jean-5633 5 жыл бұрын

Thanks for everything I have a question where did you get the 1 how did it change by sine on the second exercise,the one in the middle bottom

@ProfessorDaveExplains 5 жыл бұрын

sorry i'm not sure what you're referring to.

@jean-5633 5 жыл бұрын

@@ProfessorDaveExplains on checking comprehension. I didn't understand the one in the middle in where you replace the - sine by 1

@ProfessorDaveExplains 5 жыл бұрын

ah i see, so i factored sinx out of that difference.

@holyshit922 4 жыл бұрын

Is it really true ? What about x = kπ , where k in Z

@reinazushi 5 жыл бұрын

thank you so much for helping me with my stupid math homework ahhhhhh!!!!!

@user-hv6ef9ie1g 6 ай бұрын

5:30 Aren't we supposed to multiply both sides of the equation by 1-sin x/1-sinx? or am i missing something here?

@egonspenglercore 6 ай бұрын

I think it's because anything over itself is 1, so he doesn't show it because it's just saying 2secx(1), and (1-sinx)/(1-sinx)=1

@blessedkutsirayi9262 4 жыл бұрын

Now I'm ready for my test tomorrow

@namp2018 Жыл бұрын

in the checking comprehesion section, the last equation went from sin x - (sin x)(cos² x) to sin x - (1 - cos² x) may I ask how and why?

@cherrynuht Жыл бұрын

sorry for the late response to this comment!!!!!! what he did was factor out what both sides of the subtraction side had, being the sinx, that is why there is now a 1 as well. This makes it easier to turn the (1-cos^2x) into the sin^2x

@jeanne5067 10 ай бұрын

@@cherrynuhtHi, I am struggling with that question too, would that be possible for you to write it down because I still don't understand? sin x - sin x cos^2x = sin x/sinx - sinx/sinx • cos^2x ??

@heliomiranda9622 9 ай бұрын

This is because if you calculate [sin(x)(1 - cos^2(x))] you will get exactly [sin(x) - sin(x)cos^2(x)]... then it is just a different way (though factor out both sin(x)) to represent the same thing... but now it will have the [1 - cos^2(x)] which can be converted to [sin^2(x)] that multiplied by the remaining [sin(x)] will give [sin^3(x)] on the left side. To end: [sin^3(x) = sin^3(x)]. It is the same as [a - ax] => a(1 - x).

@thvtsydneylyf3th077 4 жыл бұрын

cheers professor ur like some god of maths or something, ty

@gabrielcx16 3 жыл бұрын

Is that a rule of trig when you multiplied cosx times cosx/cosx? Are you allowed to pull out that fraction when necessary?

@ProfessorDaveExplains 3 жыл бұрын

well you can always multiply anything by 1

@gabrielcx16 3 жыл бұрын

@@ProfessorDaveExplains ohhhhh I see how cosx/cosx= 1, in that case yea I see how you can multiply anything by 1. Thank you a lot

@jessicamateo-lorenzo748 4 жыл бұрын

Thank you so much for this video!!! you're helping me understand trig identities much better than my teacher.

@matiasjacobsen2647 5 жыл бұрын

awesome video

@Billsomebody89 9 ай бұрын

I like the subtle comprehension tests. Sadly, i can't seem to comprehend the majority of this chapter. A bit frustrating seeing how important this is for calculus. I think im having such trouble because its highly focused on vocabulary turned equation. Im pretty sure my left temporal lobectamy amplifies the difficultly. Seeing as how that is where we keep our vocabulary.

@Exonorm27 2 жыл бұрын

I’m probably weird for this, but I loved this part of Trigonometry. Everything else in trig was boring, or irritating but this was actually really fun 😂

@vanitas5097 10 ай бұрын

yes indeed u are weird... proving geometry is easier than this for me

@adweita990 6 ай бұрын

i was terrible at this in 10th grade. now in 12th- i have been academically inactive for 2 years and i got these in one go. maybe it was just the way it was taught and mindfulness back then!

@kavyamorya1258 5 жыл бұрын

I wish u were there when I was in 10th std.trignometry was my nightmare.But it's kk I still need them.

@DanielS-ev3fm 5 жыл бұрын

I literally have finals tmr I'm hopeing I'll get Tru this

@mechagear4819 4 жыл бұрын

how did they turn out?

@DanielS-ev3fm 4 жыл бұрын

@@mechagear4819 Passed! :)

@uhuhjones6088 3 жыл бұрын

Daniel S good job

@hanasiyum2879 2 жыл бұрын

Thanks it is cool

@manusaini13 5 жыл бұрын

7:59

@46-firozc73 5 жыл бұрын

Sir instead of using trig formula to solve the problem can we use this strategy? Pls reply

@ProfessorDaveExplains 5 жыл бұрын

sorry i don't understand the question

@46-firozc73 5 жыл бұрын

@@ProfessorDaveExplains Sir how can i contact you to ask my doubts?

@ProfessorDaveExplains 5 жыл бұрын

email is best

@silvershard8009 Жыл бұрын

At least a thousand times better than my Math teacher and he did it in minutes

@littleretroship6403 2 жыл бұрын

Man! There are so many relations between the different functions.

@tGoldenPhoenix 2 жыл бұрын

Done.

@cubixmem Жыл бұрын

With this video, I ain't failing the test no more

@iprovedthem5527 2 жыл бұрын

Since the video is a little old, you may not see this, but on the second example where you said multiplying cos x by cos x/cos x seemed arbitrary it looks more like cheating to make the process work. I'm 20 years out of school working through a trig unit for a home learning course so I can go to University and I see a lot of this kind of thing in my course material and none of it gets explained. How is it that you can do that without multiplying the other side of the equation as well? I know I probably look super dumb right now, but Maths is hard!

@ProfessorDaveExplains 2 жыл бұрын

You can multiply anything by 1 without changing its value, and anything over itself equals one.

@iprovedthem5527 2 жыл бұрын

@@ProfessorDaveExplains Wow, that was fast. Thank you and I now feel super dumb because that is so obvious.💪🧠

@haimharar6741 2 жыл бұрын

in the third question in the comprehension it need to be a plus rather than minus i think

@harrisonkrieger7029 5 жыл бұрын

@3:43 -- isn't that a Pythagorean Identity in and of itself?

@ProfessorDaveExplains 5 жыл бұрын

yep! just proving it

@anchoi3662 3 ай бұрын

I'm not all the way there yet but at least I'm not just staring at the paper anymore so thank you 🙏

@eddyrajan3523 4 жыл бұрын

There’s one thats like TanA= secA/cscA Help?😞

@ProfessorDaveExplains 4 жыл бұрын

convert them into sines and cosines and it'll become clear

@spica3132 2 жыл бұрын

thaaaank yoooouuuu veeerryyyy muuuccccchhh!

@user-pz5di2gk6v 4 жыл бұрын

It looks so easy now

@chokelit4148 4 жыл бұрын

Im failed many times but im never give up then my 3rd try its correct

@lovemorejunior4304 6 жыл бұрын

i like the tutorial

@andresarciniegas3305 20 күн бұрын

This man cooked so much in this video, and I am so cooked in this test

@jorgecapitao1435 Жыл бұрын

I LOOOOOVE YOU FOR GOD SAKE THANK YOU SO MUCH YOU SAVED ME FROM MY USELESS TEACHER

@Kim-mq1qm 2 жыл бұрын

2:57

@adolfocarrillo248 5 жыл бұрын

In min 6:10 Why "2 sec X = 2 / cos X"

@adolfocarrillo248 5 жыл бұрын

Oh I see why, "sec X = 1 / cos X"

@adolfocarrillo248 5 жыл бұрын

Thanks professor, Happy Birthday.😁😅😫

@user-jj4zb5jd6r 5 жыл бұрын

You will never understand how much your videos have helped me, you’ve literally saved me from killing myself

@quickhorse5489 5 жыл бұрын

في عرب هون

@user-jj4zb5jd6r 5 жыл бұрын

العرب في أي مكان

@Duck-wb8rf 6 жыл бұрын

Wow, you know a lot about all kinds of stuff, KONNOO DIIOO DAA!!!!, understands.

@karlkrueger3142 5 жыл бұрын

Found the content helpful, but it didn't really help me with the practice problems at the end.

@1emnL 3 жыл бұрын

watching this right before my test pls pray for me

@SuperMan-uj7dh 6 жыл бұрын

Hi professor!

@ProfessorDaveExplains 6 жыл бұрын

hello!

@SuperMan-uj7dh 6 жыл бұрын

Professor Dave Explains I'm glad you replied! Your channel helps me a lot with school! Thank you!

@lalmuanpuii7190 Жыл бұрын

this is class 10 level right? i was searching for class 12 🥲

@elrinesporlas296 4 жыл бұрын

Farquad be teaching math now

@Pngmade675 2 жыл бұрын

I find the writings highlighted in black quite irritating

@mypenisisincrediblysmallbu5538 3 жыл бұрын

did anyone elses teacher tell them to strictly change one side only?

@ambulance2793 6 жыл бұрын

Even Speedwagon understands.

@ivoryas1696 2 жыл бұрын

Ambulance He does? *_Niiiiiiiiiceu_*

@clive_clive 5 жыл бұрын

too sleepy to learn

@isaacgordon6259 3 жыл бұрын

It made sense up until the second example...imma fail this test

@josephshim2442 4 жыл бұрын

I dig the chest hair

@Displ4c 4 жыл бұрын

I’m not very smart so this is hard asf

@champsinger 8 ай бұрын

@khconlineeducation 6 жыл бұрын

👍👍👍👍👍👍👍👍

@phoebe7918 3 жыл бұрын

That easiest questions I never see on tri ident...

@Yui_Fukushima0104 6 жыл бұрын

Goddamit this. Trig identities is the hell of my life

@imj9581 6 жыл бұрын

6:17 "since these are just 'sooo' fun" why does it sound like even he is admitting these are not fun XD

@ProfessorDaveExplains 6 жыл бұрын

haha i guess it does come off sounding a little sarcastic but i do genuinely think these are super fun!

@alkynegaming7400 5 жыл бұрын

Lmao

@naveensundar4765 4 жыл бұрын

LMAO

@Kurt4014 2 ай бұрын

Bagsak nako bukas

@ahmadyasin257 4 жыл бұрын

How many of you all just see the working and don't do them themselves....ha ha ah ah a..Welcome to the group...

@ouma2368 2 жыл бұрын

for 10 points :>

@donutthephuan7231 4 жыл бұрын

Anybody else stuck doing trig in quarantine?

@masauso8523 2 жыл бұрын

Jesus has saved my CA again 👏👏👏

@calistavicente-bradley4739 4 жыл бұрын

Still makes no sense

@vanessah4943 4 жыл бұрын

Why do I have to know this...ugh

@shayanthanjack8994 6 жыл бұрын

this video didnt help at all