Derivative of sec(x) from first principles (definition)

In this video I showed how to use the definition of the derivative to find the deriative of sec(x)

[@lyricaltherapist2994]

I don't know if I should call you bro or teacher, bt the truth is that you are undoubtedly amazing 💯

[@aphelmusonda5253]

you're very strong sir, i enjoyed your courage and smiles when explaining the concepts, thank you very much (watching from Zambia)

[@PrimeNewtons]

Thanks 😊

[@PatrickEteuati]

Explain this better than my lecturer at University. Thank you, blessed.

[@shortsking9494]

i am from india i understood completely loved the video

[@moamysteriesofactivities2087]

Watching from Pakistan 🇵🇰, you are such a helpful person for student who are studying calculas after completing intermediate in medical 😅,

[@LexiTRexy]

i was so confused thank you so much I was about to cry about this problem but you solved it so easily! ahhhh thank you!!

[@chrisjuravich3398]

Excellent presentation, sir. Very helpful and encouraging.

[@nanamacapagal8342]

i noticed something: by 3:06, instead of using identities, you can just factor out (1/h)(cos(x) - cos(x+h)), and notice that this is just definition of the derivative (almost... it's negative instead) of cos(x). So now you're left with -(-sin(x)) * lim_h->0 (1/cos(x)cos(x+h)) = sin(x) * sec^2(x) = sec(x)tan(x) Same can be done with the derivative of cosecant!

[@takudzwajoezaza6467]

very easy to understand. thank you for such a lovely video

[@EzraSchroeder]

so good, so satisfying!

[@IrvinMoonga-rw4ul]

You are the exact definition of simplicity 😮

[@PauloDacosta-s1s]

I wish to know if (1-cosx)/x =0 or (cosx -1)/x =0. I am asking because you use the first relation in this video and in the video of sinx, you used the second relation. I know that you just need to multiply the second equation by -1 to solve the problem but I wish to know exactly which is the right relation…. Thanks in advance….anyway, your videos are quite good

[@PrimeNewtons]

The limits are both zero.

[@talentgoldenmanyika9763]

youre the best💯💯💯💯

[@PrimeNewtons]

I really want this to be true. Still learning 😊

[@talentgoldenmanyika9763]

one day l wiill be best as you🤪🤪@@PrimeNewtons

[@klineoware]

I stumbled over a sign issue this helped me realise where I went wrong

[@matthewdaniel1715]

Same with me

[@sidratulmuntaha6914]

Amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing amazing 🤩

[@hossammohammed1458]

you are my hero sir

[@Lukas-mq3vv]

GOAT thanks for the video

[@TheArchit1]

Nice video.

[@donaldmachele2854]

Sir what happened on the sign issue?

[@quocanhpham5449]

Thank u!

[@shortsking9494]

you are from which country

[@PrimeNewtons]

Nigeria

[@punditgi]

This one also! 🤩

[@b.pradhan9359]

[@لاإلاهإلااللهمحمدرسولالله-ج3س]

😊😊😊

[@joshuaabiamowei2453]

what of 1/cosx

[@PrimeNewtons]

1/cosx = sec x

[@lightff8664]

sorry me ! i had already done upto last 2nd line then tore my page thinking i got it worng . then searched for this vid and wow i really am stupid

[@navantprakash1304]

🐒