Grade 12 Calculus Lesson 3 | Factorising Cubic Functions | Mlungisi Nkosi

#mlungisinkosi #grade12 #matric

[@tshepanglephale2210]

Starting prelims in 5days😭😭😭😭😭😭your videos are great Sir!😭😭🤝

[@beatalabercensie2174]

Trial exams starting next week...rewatching these videos for revision. Thank you so much sir for all your help. You are a blessing ❤️❤️ Love from the Eastern Cape

[@MlungisiNkosi]

My pleasure 😌

[@kamogelomodjadji4005]

One of the best teachers in South Africa😎

[@MlungisiNkosi]

Thank you 😊

[@Mei2.0]

to find the middle term in the long bracket the alternative is to use the "b" rule, equating the squared value of "b" to the bx2 value in the equation. It's available on the mind action series page 154

[@MlungisiNkosi]

Yes I eventually used it

[@tambiraimuduma4601]

thank you very much sir ,you`re a truly a life saver, your pysics and maths lessons do it for me.😊

[@rasealalebogang6176]

I was struggling alot when coming to this part ,but now im cool with it , thanks😊

[@ntsitselelemirriam1116]

Never thought factoring cubic is so easy ♥️

[@MlungisiNkosi]

Thank you 😊

[@zanonoza4918]

Mlu , you're good at this baba . Keep shining. It's your calling ❤

[@ChunSwaeRrrr]

Hi sir , i believe there are sometimes two values that can give you zero when you substitute to get zero in the very 1st equation cause I tried (+3) and it worked but when I had to simplify the equation it didn’t balance out like the (-1) so I encourage the learners to try and see if they can get 2 values equating to zero cause one can feel stuck

[@MlungisiNkosi]

I get you…. You’re right

[@Enzyy_1X]

i am loving your series so far, at least understanding. Thank you once again

[@MlungisiNkosi]

You’re welcome

[@user-en4ze5xe3c]

I just subscribed to your channel a week ago, and I have watched Grade 12 Calculus Lessons 3 and 4 a few times now and I still don't understand how you factored the quadratic portion of f(x) = X^3+4X^2-11X-30. I see how you found the first factor (X+2) but you have to find a better way to show how you found the second factor (X^2+2X-15) -- especially the middle value (2X). Can you make a new video, if you don't have one already, showing the process by itself step by step? Thay would be great, Thanks. Also - lesson 4 is way too long.

[@MlungisiNkosi]

Thank you for the feedback ❤️

[@nosiphoprecioussopekisi721]

You are such a life savior Bab' Mlu🤗

[@MlungisiNkosi]

Ngiyabonga ngane yami 🫡

[@nonhlanhlamoloi5250]

This Is the best . Been struggling alot with cubic funtions for sometime now and I'm finally seeing the light, Thank you sir🙏

[@MlungisiNkosi]

You're welcome

[@tasteafrica1562]

Casio calculator 991 does it for you

[@Tshilidzi.m-yd2jk]

Thank you sir,I was struggling with this but now I got the skill and it's the easiest.❤️

[@mueededross3540]

13:53 does x not = -2 as it was (x + 2 ) in the bracket and for the next example when u brought it out you did change the sign?

[@MlungisiNkosi]

Thank you

[@lunganindlela4806]

Yes it does the signs were suppose to change

[@lee.thaboo]

On the 2nd example if you're confused as i was when we had to find the middle term in the trinomial -Its actually "x multiplied by which number gives you 7x^2" not "1 multiplied by which number because then you wouldn't get 7x^2." I think our fave uncle made a mistake there but its okay he taught us well enough to recognise and find what was incorrect regardless lol🎀

[@tandzilematsenjwa9811]

Finding the middle term is a bit tricky but as I will be practising I hope it will be easier..

[@MlungisiNkosi]

How are you finding it now?

[@queenmohoera3194]

I have a question sir... should we always use 1,-1,2,-2 etc... When finding the factors?

[@MlungisiNkosi]

Yes

[@lindokuhlenkosi8238]

You are honestly the best.❤️

[@MlungisiNkosi]

Dankie Mlindos

[@GibsonMogale]

So after getting the factor will I be penalised for using this formula👇 (X+1)(x²+bx+c) Then from the I get rid of the brackets using the original equation Don't know if I make sense🤧🤧🤷‍♂️🤷‍♂️

[@MlungisiNkosi]

I understand what you mean. No you won’t be penalised if you do it correctly

[@owamlingani3368]

x- 3 is also a factor . Should we use the factor that we found first ?

[@MlungisiNkosi]

Absolutely and you still end up at the same place anyway

[@rachealnkosi8567]

Had forgotten this thank you for the reminder

[@MlungisiNkosi]

You’re welcome

[@jin00305]

27:07 Very much sir 💥

[@MlungisiNkosi]

You’re welcome ❤️

[@Tizozo_M22]

Isn't in the equation to sole for cubic for the first example where we found -2 would equal to 0 to get x - intercept so it's going to be x+2=0 for one bracket but as a intercept its 2

[@THE_MUSKETEERS016]

For the last cubic function X³-12x²+36x I got x-6 as a factor

[@MlungisiNkosi]

Awesome 😎

[@sithembisilekumane246]

This method is not the same as that one of long division but it looks like it's easy to work with

[@Fine559]

Instead of saying X=0 at 22:38 I substituted into X like you have been doing and the only number that gave me 0 was 6 and so I said X-6 is a factor but I still got the same answer, I have a really good feeling that I'm wrong because I feel like you can't use a big number like 6 as a factor, am I wrong sir?

[@MlungisiNkosi]

That sounds correct though… But how come you skipped all the other numbers and went for 6? I’m trying to understand your process…

[@Fine559]

@@MlungisiNkosi I kept substituting from one, until I got to 6

[@gradimukwasa1386]

Great video, i liked how you use the synthetic division. Very well explained

[@MlungisiNkosi]

Thank you 🙏🏾

[@siyasangatatsi6079]

Thank you so much Sir 🙌🏽

[@MlungisiNkosi]

You’re welcome

[@DelisaWonder]

Finding the middle term is a bit tricky

[@MlungisiNkosi]

It does take a bit of getting used to

[@roselinemante5111]

Thanks you 🔥

[@MlungisiNkosi]

My pleasure

[@awesomemovieclips9268]

I do my synthetic in a table form.so much easier

[@MlungisiNkosi]

The point is that you have something that works… I’m happy 😊

[@sarahadem7774]

❤❤

[@MlungisiNkosi]

😍

[@rachealnkosi8567]

There is a vid in physics where you dropped your WhatsApp number but I can't find it please share them .🙏

[@MlungisiNkosi]

Please check it on my KZbin page

[@user-mh6pb4be3b]

Hi did you find it ,if u did pliz share l want it ❤

[@cynthiamakhumo9966]

Hello sir may you please do September 2020 question paper from free state questions 8 calculus question please

[@MlungisiNkosi]

Where may I find it?

[@yonelamashiyi3186]

Sir...your videos help me a lot, thank you🙏❤...but I'm not gonna lie... Synthetic Division is WAYY easier than this.

[@MlungisiNkosi]

As they say different strokes for different folks… I’m glad I could help though.

[@tshepangnicole7755]

Can u kindly use another formula.

[@MlungisiNkosi]

For what?

[@tshepangnicole7755]

@@MlungisiNkosi synthetic division