A-Level Maths: B7-10 Graphs: Solving Modulus Inequalities

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[@nuruladlina7674]

I NOW UNDERSTAND THIS STUFF!! AAAA MUCH THANK UUUUU

[@jordansheridan5325]

You have boosted my A level grade from a D to almost full marks! It would be amazing if you could make a mechanics 1 ocr mei videos

[@TLMaths]

I'm not teaching that module I'm afraid, so I won't be making them - my focus is on the new A-Level spec ready for September. Apologies.

[@quietworld6870]

My exam is tmrw n now I understand 🤦‍♀️🤦‍♀️

[@realroshrosh]

This guy deserves more subscribers

[@Rachel-xi7be]

thano you soooo much for this❤️

[@iuseyoutubealot]

how would i solve |2x+1|+|2x+1|=3 ;do i bring one of |2x+1| to the RHS to start

[@TLMaths]

Surely that will simplify to 2*|2x+1| = 3 |2x+1| = 3/2 ...?

[@aryansapkota6796]

|2x+1| + |2x+1|= 3 or -3 , remove mod signs and solve both equations, x= 1/4 or -5/4

[@afghanclick3811]

hi can you make a video about, some tricky exam questions in AQA C1 and C2 please.

[@TLMaths]

I don't do any more AQA specific videos I'm afraid - I'm focusing solely on the new specification

[@afghanclick3811]

Alright Thank you

[@Ash-en4ul]

When yoy are calulcating it and like changing the signs to acocomodate for the negative gradient, would you change the graident of the eg make it from 2x+3 to =2x+3 , or do you change the value its equal to eg, 2x+3= 4 ; is it -2x+3= 4 or is it 2x+3= -4? Thanks

[@TLMaths]

You change the sign of anything that is in the modulus sign, so for |2x+3|, you look at -(2x+3) = -2x-3

[@Ash-en4ul]

@@TLMaths thanks!! Do you know where I can get questions that merge ln concepts and Modulus together?? Thanks I know it's oddly specific

[@sharkm0m0]

Hello. How can we make the decision which values to take after obtaining x without graphing?

[@devrohilla7978]

I am indian but love this content very much

[@augustinezulu6143]

So the signs changes if the line is going to the left side only?

[@augustinezulu6143]

I'm confused on the last question

[@TLMaths]

The left hand part of the graph has negative gradient, so will be y = -3x + 7, and the right hand part of the graph has positive gradient so will be y = 3x - 7

[@danielfontain150]

Hi. I saw in a question that said |6-x|=1/2x + k. And Has exactly one soloution. Find the value of K. I dont understand why the intersection has to be in the vortex, so (6,0). Surely it can be anywhere in |6-x|.

[@TLMaths]

It's probably easier to visualise it on desmos: www.desmos.com/calculator/hvoztrllg9 You can then use the slider for k to see how this changes things. Clearly if there is to be only one intersection point, the line will have to intersect the modulus graph at the vertex.

[@danielfontain150]

@@TLMaths Ah ok I see. Thanks for the link. I didnt take the graident into account. Cheers sir!

[@aryansapkota6796]

Is k= -3? What i did was uno that 6-x= + or - (1/2x+k) . Rearranged one of the equations for K. Substitute into the other equation to solve for x which i got as 6 and then plug back into one of the equations, k = -3 (like simultaneous equations)

[@korypolexa3714]

I don't get how for number two the y intersect is positive 5 if it was -5

[@TLMaths]

|2x-5| Sub in x=0 |2*0-5| = |-5| = 5

[@ronedavin7573]

I don't understand why for the second question the line touch +ve 5 instead of -5. I'm don't understand this part...Please Help me i'm really confuse

[@TLMaths]

The outputs of the modulus function are always greater than or equal to zero, so |f(x)| is always above or on the x-axis. The graph of y = |2x - 5| doesn't go below the x-axis for this very reason. Think of it like the line y = 2x -5 but everything that has gone below the x-axis has been reflected up in the x-axis. See: www.desmos.com/calculator/utgpjs5blz

[@muhammadizhan2741]

Good techar tomorow my papar gud bcz of u sar thank you

[@tz6011]

Thanks for your videos!

[@JK-vm7yo]

How come for the first question we put a minus sign on the 1 and not the 2x-7 ?

[@TLMaths]

When solving |2x-7| = 1, you can consider that either 2x-7 = 1 or 2x-7 = -1 because |1| = 1 and |-1| = 1

[@مرتضیافغان-ك3ض]

can you make a video about, how to study or get an A in AQA a level maths. because I am revising a lot but can't do good enough in the exam please please

[@TLMaths]

What sort of revision are you doing?

[@مرتضیافغان-ك3ض]

I doing post exam papers, and watching KZbin video, I did 2016 c2 Peper today and I thought i will get a good result but I think I did bad

[@مرتضیافغان-ك3ض]

sorry about my English writing, I am not good in English

[@TLMaths]

Use www.physicsandmathstutor.com/a-level-maths-papers/ to get your papers - and don';t be afraid to dip into other exam boards for C1 and C2 - they're all useful. You need to work through all the papers of the board you are sitting - make sure you record which ones you have done and the score you got each time (you want to see progress and improvement). You will need to mark yourself using the mark scheme, and be harsh - this will get you used to what the examiner is looking for. Time yourself also - you want to train yourself to work at pace so that you don't run out of time in the exam. Write lists of the topics you continue to struggle on and add to this after every paper you complete - these topics will require more emphasis in your study. Watch videos on these and ask your teacher for help. Seek help from somebody else studying the exam or who is in their second year, or even a tutor - the one-to-one opportunity to ask for help is invaluable. Ultimately, you need to know what you don't know. If you sit down to do a paper and you think it went well, when in fact it didn't, then you'll not be in a good position. You need to constantly give yourself short low-stakes tests so that you can determine what you do and don't know. Break your revision up into chunks and interleave topics (don't do two hours of polynomials), do half an hour of one topic, then have a break, then half an hour of another topic, then a break, then half an hour of another topic. Try writing out a crib sheet - can you fit everything you need to remember about Core 1 onto a single side of A4 for example? This test of memory forces you to remember topics and concepts and is good for brain-training.

[@مرتضیافغان-ك3ض]

Thanks

[@Phoenix-nh9kt]

But how do i solve questions wherein y is inside the modulus along with x

[@TLMaths]

Can you give an example and where you’ve seen it in A-Level Maths?

[@darosaleh830]

Are you gonna make mechanics videos by the end of may?

[@TLMaths]

No, I'm afraid not - I won't be that far along

[@davidhill8163]

Many thanks I find this topic kinda tricky

[@kel7397]

ty sir

[@Mostpeoplecant]

cheers