You are very welcome, friend. Thank you for leaving your message. Kind regards from Australia.
@atonio247611 күн бұрын
To calculate percentages with £sd, such as a 10% discount, you would convert the whole sum; eg £8 5s 4d into pence, remembering there are 240 pennies to the pound, and 12 pence to the shilling. (240 by 8 = 1920 + 60 + 4 = 1984) 10% of 1984 is 198. Convert this figure back ( 16s/6d) and subtract from the original sum. This is £7/8s/10d.
@CrystalClearMaths11 күн бұрын
That is definitely one way to perform the calculation, Antonio! Another would be to calculate 10% of £8 (which equals 160 shillings) ... i.e. 16 shillings. Then one could calculate 10% of 5s 4d (which equals 64 pence) ... i.e. 6.4 pence. The total would be 16s 4d, and one would proceed in the same way that you described. Which method would be more appropriate would depend largely on the figures involved (and how one felt at the time). Thank you very much for your helpful contribution!
@atonio247610 күн бұрын
@@CrystalClearMaths Your method sounds a lot better, in separating pounds from shillings and pence, and I will try to memorise it. I didn't realise how straightforward it was, and thought that's why the £sd system was abandoned. I can calculate percentages mentally using your method. I bought an old pre 1971 arithmetic book, via ebay, to practise the maths. I've improved my arithmetic skills since doing this: I've memorised the 12 times table, and all the times-tables as we did when children at school. The half-crown was 2s/6d, (12.5 new pence) and there were 8 to a pound. A guinea is 21 shillings. There are four farthings to a penny.
@CrystalClearMaths9 күн бұрын
@@atonio2476 I am glad that you have been discovering all this, Atonio. In some ways, it is quite an enjoyable exercise (changing bases between measurements). Thank you for your reflections.
@atonio24768 күн бұрын
@@CrystalClearMaths We weren't told about the older system at school, and would have benefited from one lesson, to familiarise us. The 'shilling' is a feature in older literature such as Charles Dickens, and this cultural aspect has been lost with decimalisation. I find that with decimal addition, the loss of the shilling creates a gap in the psychological processes.
@CrystalClearMaths8 күн бұрын
@@atonio2476 I agree. It is mathematically (arithmetically) beneficial to learn other base systems and culturally and historically important to be aware of these measurements, too. I enjoyvreading historical books and it helps hugely when we understand references like 'shillings.' Thank you for your important observation.
@shannonsmith29716 күн бұрын
Nine
@Editwithanisha-rx1nv26 күн бұрын
Wow nice teaching grandfather ❤
@CrystalClearMaths26 күн бұрын
Hehehehe ... thank you :-).
@ockham196328 күн бұрын
brilliant explanations here and in your other videos
@CrystalClearMaths27 күн бұрын
Thank you, kindly, John. I greatly appreciate your encouragement, and am glad that you are finding worthwhile things on this channel. Kind regards, Graeme
@komitetgosudarstvennoybezo521629 күн бұрын
Knowledge and concepts never get old to be applied anyway fr,thank yuh sir
@CrystalClearMaths29 күн бұрын
You are welcome, Komitet Gosudarstvennoy Bezopasnosti, and thank you for your observation. Kind regards to you from Australia.
@komitetgosudarstvennoybezo521625 күн бұрын
@@CrystalClearMaths sir yuh still active here,how’s life going for ya
@CrystalClearMaths11 күн бұрын
@@komitetgosudarstvennoybezo5216 A few ongoing challenges, K. Thank you for asking. I am still responding to comments, but have some significant matters in real life to sort out before I can see my way clear to resume posting videos. I am sorry. Kind regards to you, and thank you very much for your support and concern. Both are appreciated!
@user-te1zk1rm2uАй бұрын
f is negative quartic graph, power n=4, so f' is cubic graph. power n=3. but lecturer draw a strange graph and power n over 4. that's misleading students.
@CrystalClearMathsАй бұрын
The second graph certainly LOOKS like a negative quartic graph, but it is not necessarily one. I randomly sketched it and no formula was provided. The object of the video was to explain and teach a principle or method for sketching gradient functions when the formula for the original function is unknown. It is quite possible for a graph of that shape (not a negative quartic) to have a gradient function as I depicted. You are, however, quite correct in this ... IF it was a negative quartic graph, the derivative function would most certainly be a cubic function.
@28.tranthithaophuong-lt-n27Ай бұрын
Why must the expression equal 0
@CrystalClearMathsАй бұрын
Because the equation for the x-axis is y = 0. When we set y = 0, we are solving two equations simultaneously ... that of the polynomial (or any function for that matter), and the line y = 0. The results are all the points where the polynomial crosses or touches the x-axis (i.e. the points of intersection). Algebraically, we refer to these values as the 'roots' or 'zeros' of the polynomial. Graphically, they are simply referred to as x-intercepts. Thank you for asking, Tran.
@wrj9221Ай бұрын
I am writing to tell you that your website is not working properly...june 18 2024
@CrystalClearMathsАй бұрын
Thank you very much, Jim. I have been unwell and have not been monitoring my website for some time. I appreciate your drawing my attention to it and will try to rectify the matter asap. Kind regards to you. Graeme
@arshantv3579Ай бұрын
Salute u master (sir) My question is what isRichard Feynman’s Integral Trick and how he invented this trick And my 2nd question is Why u r not making new videos for your lovely students Im waiting for your new video plzzz for god sake
@CrystalClearMathsАй бұрын
Greetings, Arshan. Thank you very much for your questions. Unfortunately, I have been dealing with a long list of family matters (currently I am dealing with cancer). This has kept me from making videos for years. I still hope to resume working on them, but need to get my health re-established first. I am sorry. I have seen some quite good KZfaq videos in the past about Richard Feynman's integral technique. It is quite ingenious and, if you search KZfaq for them, you will find good explanations in that way. Sadly, I do not have the resources at the moment to help you with this matter. I greatly appreciate your concern and interest and hope to be able to produce videos again 'soon.' Kind regards to you!
@Jess.is.a.mess_08Ай бұрын
Thank you so much sir, I'll put these tips into action from now on and let you know if I improve 😊
@CrystalClearMathsАй бұрын
I would love to hear how you go, Bubblepop, thank you. I am glad that my suggestions have made sense to you and very much appreciate your making contact and telling me about it! Warm regards to you. Graeme
@Jess.is.a.mess_08Ай бұрын
@@CrystalClearMaths Dear sir, these suggestions magically worked for me I got 29/30 in my latest math test... I hope to continue this marks for the upcoming tests also. Thank you again 😊
@CrystalClearMathsАй бұрын
@@Jess.is.a.mess_08 That is brilliant and exciting news, Bubblepop! Congratulations! I very much appreciate your letting me know of your results. I am glad that my suggestions helped you, and wish you every success for the future.
@Jess.is.a.mess_08Ай бұрын
@@CrystalClearMaths thank you sir, I'll work very hard from now on!!
@carvelbell181Ай бұрын
Your tutorials are excellent. I love your channels, excellent teaching techniqiues, it help me to see and learn concept clearly.
@CrystalClearMathsАй бұрын
Thank you, carvelbell181. I am glad that my videos help you 'see and learn concepts clearly.' That is a great encouragement to me. May you always continue to enjoy learning. Warm wishes to you. Graeme
@theworldofcreativity9071Ай бұрын
wait what happens if in the calculating the difference part we get a number>10?
@CrystalClearMathsАй бұрын
Occasionally, that happens. It is simply an estimate. In that case, choose 9 and see if it 'works.' This is not an exact predictive method. It is an iterative process using approximations. Thank you for seeking clarity, WoC. Sometimes, the first approximation needs to be adjusted.
@c.m.p2943Ай бұрын
Thank you sir
@CrystalClearMathsАй бұрын
You are welcome, CMP.
@sillymesilly2 ай бұрын
I would say Babylonian method be easier?
@CrystalClearMathsАй бұрын
It very likely would be ... a good iterative technique. Thank you for your astute observation, Silly Me Silly.
@ivanradoszyce81832 ай бұрын
I think and easier way was is to factor x^2 from under the square root and the let u = a/x, which means du = -a/x^2 dx. Then it becomes a simple log solution.
@CrystalClearMathsАй бұрын
I agree, Ivan. When I started producing this series, I was intent on demonstrating and teaching particular substitution techniques and realise that, for a number of the integrals, I therefore adopted a less efficient method of arriving at a satisfactory answer. I left the videos because the primary objective was still achieved ... that of showing how to use certain trigonometric substitutions. Students facing this question during an examination would be well advised to adopt the method that you describe so well! Thank you.
@vidhyamadhavan19892 ай бұрын
Hello Mr Graeme, I'm a special educator. How do I create that interest in a child who likes solving problems but dislikes the uncomfortable feeling of solving challenging problems?
@CrystalClearMaths2 ай бұрын
Greetings, Vidhya. You have asked a very interesting question. Thank you. Not all children will respond to the "uncomfortable feeling of solving challenging problems." I think of it like asking children to run or hike up a tall hill or mountain, or to engage in a multi-day hike. Some children respond positively. Some do not. I have taken reluctant children on a multi-day hike or had them camp alone in the 'bush' for a night and had some of them respond extremely positively. I believe it is because they realise that they have succeeded at something big and momentous ... something that they did not believe that they could do (or wanted to do). In all cases, I believe it was MY PARTICIPATION and ENCOURAGEMENT at all steps that made the difference. Their sense of achievement is what may motivate them to engage in future challenges. In the case of mathematical problems, I do not leave them alone (at first). If they struggle and are on the verge of 'giving up,' I ask a QUESTION. Good leading questions lead to discussions that allow them to make discoveries, so that they can take another step. Finally, when they reach the goal and solve the difficult problem, I am full of PRAISE for their achievement. I will tell others and tell their parents (and, sometimes, though rarely, provide a extra reward). You will not win with everyone (as not everyone will develop a passion for mathematics), but your successes will sustain you ... and you will profoundly help and motivate some students.
@rajeshgupta-hm3iy2 ай бұрын
I appreciate❤
@CrystalClearMaths2 ай бұрын
Thank you, Rajesh. I greatly appreciate your feedback, too. Kind regards, Graeme
@ToddlerKicker2 ай бұрын
I have the biggest exam I have in the last 16 years of life, I am a nervous wreck, I really need this A for my math. Thank you so much for sharing your tips.
@CrystalClearMaths2 ай бұрын
I feel for you, TK, and wish you the best for this exam.
@TotoisBored2 ай бұрын
Nice video my man!
@CrystalClearMaths2 ай бұрын
Thank you!
@branflakes44292 ай бұрын
This is why Crystal Clear Maths is one of the best Mathematics channels on KZfaq. Not only does he help us with Maths, but he helps us extensively with everything else. I'm glad I found this channel.
@CrystalClearMaths2 ай бұрын
You are very kind, branflakes. Thank you. I appreciate your support. Kind wishes to you from "Down Under!"
@frankadinortey85182 ай бұрын
🎉❤😊
@frankadinortey85182 ай бұрын
❤🎉😢
@CrystalClearMaths2 ай бұрын
@@frankadinortey8518 😃
@cellotownn2 ай бұрын
Such an informative video! Even more informative than classes in 901 🎉🎉
@CrystalClearMaths2 ай бұрын
Thank you, cellotownn. Being from Australia, I am not aware of what 'classes in 901' are, but your comment is very encouraging. Kind regards and best wishes from 'Down Under.'
@theguywhoasked79622 ай бұрын
oh hi ethan
@TotoisBored2 ай бұрын
@@theguywhoasked7962 bro shut up Thomas
@liwendeng69232 ай бұрын
@@CrystalClearMaths 901 is a classroom in sydney boys high school its where we get taught pe theory and we watch your videos from there
@CrystalClearMaths2 ай бұрын
@@liwendeng6923 Thank you very much for the 'heads up.' That is helpful to know. I taught in a few schools in Sydney before moving south ... now in the Shoalhaven. I hope some of the videos are of use to you. Kind regards, CCM
@stefankramer93592 ай бұрын
Thanks for your effort, first time in years finding what I was looking to understand.
@noncompliant43162 ай бұрын
You are most welcome, Stefan. I am glad that I was able to provide what you needed. Kind regards to you (and thank you for your feedback!).
@petznassloukas71242 ай бұрын
Hope your doing well, Sir
@cheeseballs8uАй бұрын
I also hope so
@petznassloukas71242 ай бұрын
Very helpful! Preparing for my exam right now 🙏
@CrystalClearMaths2 ай бұрын
I am glad that this video helped you, petznassloukas, and hope that you do well in your exam! Kind regards to you, and thank you for providing your feedback.
@petznassloukas71242 ай бұрын
I'm here studying for finals, thanks Sir! 🙏
@CrystalClearMaths2 ай бұрын
All the best for your finals, petznassloukas ... and thank you for both your comments!
@AbhishekSingh-zc8rw2 ай бұрын
nice
@CrystalClearMaths2 ай бұрын
Thank you, Abhishek. Kind regards from CCM.
@user-bd3rs8qm9i2 ай бұрын
❤❤❤❤❤
@CrystalClearMaths2 ай бұрын
Thank you, friend. I am glad that you liked the limerick.
@theguywhoasked79622 ай бұрын
i was forced to watch this by my teacher
@CrystalClearMaths2 ай бұрын
I hope it helped, friend. I notice that you have an excellent name ... "the guy who asked." A Nobel prize winner was asked who was the greatest influence on him and his success. He replied that it was his mother, and explained that every afternoon when he arrived home from school, she never asked him if he had a good day or how he felt. She always asked, "Did you ask any good questions today?" Keep asking questions, and you will live a rich and fulfilling life. Best wishes to you from Australia (and pass my greetings on to your teacher).
@pied62 ай бұрын
How to do integral of ln(5) e ^ ln(5)x In the fourth step 3:28. I don't see how ln(5) disappeared.
@CrystalClearMaths2 ай бұрын
The ln(5) is part of the pattern. If you differentiate y = e^(ln5)x, you obtain dy/dx = ln5xe^(ln5)x. This means that integrating (finding the antiderivative of) ln5xe^(ln5)x results in e^(ln5)x + C. Thank you for asking, pied6. I hope my explanation helped.
@sometimes-xd2fl2 ай бұрын
@@CrystalClearMaths thank you for your explanation
@CrystalClearMaths2 ай бұрын
@@sometimes-xd2fl You are welcome 🙂.
@rev0cs2 ай бұрын
cheers mate
@CrystalClearMaths2 ай бұрын
Cheers to you, too, rev0cs ... 👍.
@Math-Skill_Venky2 ай бұрын
Super video sir.
@CrystalClearMaths2 ай бұрын
Thank you, Math-Skill. You are very kind.
@davea42452 ай бұрын
May the 4th...2024 🙃
@CrystalClearMaths2 ай бұрын
Another good pun! Thank you, davea4245.
@crystallising70682 ай бұрын
Thank you so much!
@CrystalClearMaths2 ай бұрын
You are welcome, crystallising7068.
@henrymcrae13723 ай бұрын
I have noticed that you haven't posted a video in many years, so I am unsure if this will reach you. I wanted to thank you for that video. I have recently moved to a Sydney boarding school from further west. I have been increasing my study efforts and have been moved up 5 math classes in my first 2 terms. I am determined to succeed in my new class and even excel beyond it. You have been a massive help, and I will be looking back at more of your videos as I progress through maths. Cheers, Henry.
@CrystalClearMaths3 ай бұрын
Henry, your message to me is most encouraging. Thank you. I am glad that you have been able to make such massive gains in your mathematics in such a short amount of time. Congratulations! I am also delighted to learn that my videos have been a help to you. I hope to resume posting videos again soon ... but have been overcoming a number of significant setbacks. Much will be revealed when I am able to resume such work. In the meantime, very best wishes to you for your studies and kind regards from the Shoalhaven (just south of Sydney).
@user-vm5yf4ul7b3 ай бұрын
Thank you sir
@CrystalClearMaths3 ай бұрын
You are welcome, user-vm5yf4ul7b. Thank you for watching my video (and for taking the time to leave your encouraging comment).
@castillomn9714 ай бұрын
Watching and hearing you in 2024 😂
@CrystalClearMaths3 ай бұрын
:-) Thank you, Castillomn971.
@Rifat.0_04 ай бұрын
awesome
@CrystalClearMaths3 ай бұрын
Thank you, Rifat. Sorry for my late reply, but I greatly appreciate your taking the time to leave your (encouraging) comment!
@user-zo3wd8ui7m4 ай бұрын
and x should come at the left side of log
@CrystalClearMaths4 ай бұрын
Unless I have seriously misunderstood you, user-zo3wd8ui7m, I don't think I agree. Perhaps you mean that the exponent could have been written x·ln(5) istead of ln(5)·x. Either would be quite satsifactory, although we do tend to write the constant before the pronumeral. Kind regards to you, and thank you for commenting.
@user-zo3wd8ui7m4 ай бұрын
the exception here is 1,as 1^x/ln 1 is undefined according to the formula. But according to the method ,we will get the correct answer that is x+C
@CrystalClearMaths4 ай бұрын
You are correct, friend. I should have pointed out that the method is quite useless if we are integrating 1^x ... but that simply reduces to 1 and the integral proceeds just as you indicated. Thank you.
@toxicdubz38414 ай бұрын
ive been practicing this rule for 1 week or so and i felt pretty stuck at the beginning, kept practicing and now i was able to do the two complicated examples near the end of the video with no guidance, thank you for being a part of my journey of learning this
@CrystalClearMaths4 ай бұрын
Thank you so much for taking the time to let me know, toxicdubz. I really appreciate your feedback and am quite encouraged that my video has helped you along your journey! Very kind regards to you, and I hope that your (mathematical) future is bright 🙂.
@majikazem69264 ай бұрын
@marvel_edits14
@majikazem69264 ай бұрын
@majikazem6926
@maryamdeen04 ай бұрын
Thank you so much sir for the crystal clear explanation! hope everything is going well for you. God bless you!
@CrystalClearMaths4 ай бұрын
Thank you very much for your encouragement, maryamdeen. God bless you, too!
@pompompurin1505 ай бұрын
I FUCKING LOVE YOU THANK YOU SO MUCH CRYSTAL CLEAR MATHS <333
@CrystalClearMaths4 ай бұрын
You are so welcome, pompompurin. I am glad that I have been able to make a difference for you (and really appreciate your support and your taking the time to let me know!). Warm regards to you from Australia (Sorry for the delay in replying ... I am a bit preoccupied with life in general atm.)
@leewilliam34175 ай бұрын
Great work 😊
@CrystalClearMaths5 ай бұрын
Thank you, Lee William. That is very kind of you.
@leewilliam34175 ай бұрын
Great work😊
@CrystalClearMaths5 ай бұрын
Thank you very much, Lee William.
@wandaadnaw45 ай бұрын
Who's watching this in 2024?
@CrystalClearMaths5 ай бұрын
I am glad that you are, wanda. I hope you found it helpful. Thank you very much for taking time to leave your comment. Kind regards from Australia 🙂.
@parokyatv22564 ай бұрын
✋
@CrystalClearMaths4 ай бұрын
@@parokyatv2256🙂Thank you.
@CrystalClearMaths4 ай бұрын
@karoldrawings5135Thank you, karold.
@rodrickluyombya69644 ай бұрын
Me
@clownphabetstrongwoman73055 ай бұрын
I know it's not a elegant method but, if use... let's call it the "guess method", I use less calculations and reach the correct answer faster. It starts like yours, with 2, then I would do 2.2⁵, 2.3⁵, maybe 2.4⁵, then try 2.31⁵, 2.32⁵, then 2.319⁵, 2.318⁵, so on and so on.
@CrystalClearMaths5 ай бұрын
For simple problems, you could try this, but for the accuracy you may want, you would need a calculator to save time. If you have a calculator to find the value of 2.318⁵, you may as well use it to find the fifth root anyway.