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## #1 Re: Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-13 03:42:35

The links that you cant see are using onenote so this time I have used a link to my dropbox account to see if it will work there

https://www.dropbox.com/s/oma5638hr15wgrr/new-work.jpg?dl=0

try this

ok thanks bobbym

## #3 Re: Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-12 04:06:53

bobbym wrote:

Hi;

Still can not get it.

Does anyone else see it?

It works for me both ways in browser and link?  Maybe that's because its on my computer etc, don't know?

## #4 Re: Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-11 22:17:37

bobbym wrote:

Hi;

That link is not coming in.

http://1drv.ms/1IRK0b9

Try to copy and paste this into your browser thanks...........

I'll try again at the link  http://1drv.ms/1IRK0b9

## #5 Re: Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-11 05:45:50

I realised after I said I had it sorted I still wasn't right so after a bit of head scratching I think I understand my mistake and the long journey getting to grips with it was worthwhile.

But......just in case I wonder would you have another look at my new working out especially the area inside the black box on top right side of page as this was where my trouble was.  I'd be really grateful if you could be critical as I want to kelp doing this the "best" or most efficient way I can and not be sloppy in my working out method, so be ruthless;-)  It still seems to be that they is probably a more elegant way.

new workings

Thanks again........

## #6 Re: Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-11 03:24:37

anonimnystefy wrote:

But, multiplying by (-4) does not change the power of x there.

aaaahh so thats part of my problem in both questions, thanks for that, but I'm a bit stuck how to work with the negative power.

I get it now and your prompting made the difference....yipppeeeee   Something for me to be very careful with moving forward

## #7 Re: Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-11 03:15:53

I multiplied by -4 to clear the Denominator of the fraction and to make the power of the other term positive, should I not have done this?

## #8 Help Me ! » Diff / equation of curve / perp problem. I can't get the textbook answ » 2015-07-10 23:52:19

silverpuma
Replies: 14

Hi, as an old codger I'm working my way through GCSE further maths textbook, self teaching myself to help my son.  The last section on Tangent and Normal have 10 questions and I have 8 of them finished and correct but these 2 I have checked and rechecked but still am making a mistake somewhere as my answer and the textbook are not the same.

No doubt it will be an embarrassingly easy fix but.....I can't see it, my 1.5 brain cells are overheating......help:-)

question and my workings

Thanks guys for any and all help.........

## #9 Re: Help Me ! » surd question help needed » 2014-04-17 06:44:08

Ok bobbym thanks and I, ll do that and post by tomorrow hopefully if holidays dont devour me up -:)

## #10 Re: Help Me ! » surd question help needed » 2014-04-17 02:26:45

Sorry for the delay.....it is a 5......thanks

## #11 Re: Help Me ! » surd question help needed » 2014-04-16 05:25:51

Thank you lots bobbym your an amazing help as I try to come to grips with all this new information.  If you haven't time to look at the second question I posted in my Dropbox no worries, im happy for help with question ,  but if you can great.....-:)

## #12 Re: Help Me ! » surd question help needed » 2014-04-15 09:48:25

https://www.dropbox.com/s/4mbvmuy64j1ym … 408_01.jpg

## #13 Re: Help Me ! » surd question help needed » 2014-04-15 09:22:35

https://www.dropbox.com/s/ddpiqt96ptjla … 447_01.jpg

The link will explain better sorry for the torturous sentence in prevoius post.....I think ive got surds flu.....agggghhhh

## #14 Help Me ! » surd question help needed » 2014-04-15 07:55:26

silverpuma
Replies: 12

Im making progress with my surds diet......yum yum but one has stuck in my throat.  I need a step by step of how you arrive at my textbook answer of 5root2 over 2  the question is ........The sq root18 minus 1 over sq root 2     thanks again for your patience.

## #15 Re: Help Me ! » standard form question I got wrong ....need some help please. » 2014-04-10 09:54:30

bobbym wrote:

Soon you will get to Absolute value and Surds, then they will combine an Absolute value and a Surd into AbSurd. Just a little geek humor.

He he.....

Even the name "surds" who thought that one up......

## #16 Re: Help Me ! » standard form question I got wrong ....need some help please. » 2014-04-10 08:36:18

Great bobbym all makes sense now. I could kick myself not getting this right but the learning goes on. Irrational and rational numbers next with surds after that yum yum.  Thanks for the help....

## #17 Help Me ! » standard form question I got wrong ....need some help please. » 2014-04-10 06:53:31

silverpuma
Replies: 5

https://www.dropbox.com/s/sn00ksxbx9hn6 … 193709.jpg

Hi guys,  I'm on standard form now and got all my exam type questions from the text book right until this last one (see above) the answer is 2167 seconds as per the answer sheet but could you show your working out for me as I must be making a wrongs step along the way.  Thanks as always

Ooops it question 4 the planets

## #18 Re: Help Me ! » Ratio question has my blood pressure in the red......-:) » 2014-04-04 06:50:22

Thanks bobbym I'll have a good think about this.  I confess it's still not overly clear in my mind.

## #19 Help Me ! » Ratio question has my blood pressure in the red......-:) » 2014-04-04 06:24:03

silverpuma
Replies: 3

Im on ratios in my working through the ccea gcse higher textbook and im really enjoying it.  ON ratios I sailed through the summary questions and exam questions without too much trouble and was happy I had a good grasp.....until.....this question stumped me.

Question: A prize is divided between three people P, Q and R.  If the ratio of P's share to Q's share is 3:1 and of Q's share to R's share is 2:5 , calculate the ratio of P's share to R's share.

The answer is 6:5 as per the book but I need someone to explain ....how...the steps to this answer is arrived at.    Many thanks for your patience with this old codger...

## #20 Re: Help Me ! » If you know the sum of the factors of a number, what the number? » 2014-03-06 16:17:04

Thanks bobbym.  So from what you said, I'm assuming that the textbook authors probably added this question to get the reader (me) to do what I did, and just figure it out with a few trys.  I enjoyed this as it made me stop and try different things albeit to no avail in the end but the ponder was good.  Though on the other hand it did leave me a bit perturbed as it looked to begin with a fairly straight forward question that after a bit of thinking through I thought I will be able to come up with a formula or number of steps to answer this question and others like it without the tests I had to do.  More of a definitive method.

I had thought I must be missing something easy since I expected the summary questions at the end of the chapter (where this question was) would have been of the type covered and explained with solutions in the pages I had finished studying.  So I quickly scanned the previous dozen pages but I still couldn't find any clarity.  It makes me aware that these type of questions might be lurking for me as I progress further....yum yum:)

## #21 Help Me ! » If you know the sum of the factors of a number, what the number? » 2014-03-06 13:33:03

silverpuma
Replies: 3

back again for help.  A another question from my textbook that although I got the answer right by trying out different numbers but I'm sure there must be a easier/faster, formula way but I can't seem to find it in the previous teaching in the text book.

The question is....The sum of the factors of x is 18.  What is x?

I found the prime factors of 18: they are 2 x 3 x 3  But I could not see how this would help me.  And after a few runs trying different numbers I found that 10 with the factors of 1, 2, 5, 10 added up to 18.  So x = 10  But there has to be a more elegant way than trying numbers until one fits especially if the question was a larger number, for example say..... The sum of the factors of x is 511.  What is x?

That would take a lot of tests before the answer.  Probably the answer is sitting in front of me but.....I think the age is showing:  thanks guys...........

## #22 Re: Help Me ! » Help with this Prime factor sq root example » 2014-03-06 03:59:54

Thanks guys for the help and after my MIF reading last night and a period of head scratching my maths question became crystal clear and I'm happy to move on to the next page on my text book.  I really enjoy this when something is fuzzy and then all of a sudden it begins to make sense.

@bob bundy   The way my son's school works is that the students study Key stage 3 over yr 8-10.  Then the majority of the year will do their maths higher GCSE over 2 years (y11 - y12).  But some who show the ability and interest (so far my son is in this group) do this GCSE higher maths in 1 year instead of 2 , at the end of y11.  Then they do this additional/further maths exam at the end of y12 so they have 2 maths qualifications during this 2 year period,  where most have the normal 1 GCSE maths qualification over 2 years.  Then they begin the normal A-Level course over 2 years. For this the school uses the edexcel A-Level course C1 C2, C2, C4 M1 and S1.

Bob you said above...

"Did you mean GCSE then 1 year extra GCSE then 2 more years A level ?  What's to stop doing the extra concurrently with year 1 A level to short cut the process?"

I think the main thing is that since this additional/further 1 year maths qualification over 1 year is a bridge to A-Levels and include subjects that are in the first year A-Level so there would be too much overlap and double learning at the same time.  But that's just me thinking out loud.

Another question just popped into my mind:-)  When finding the prime factors of large number without a calculator I noticed that sometimes I would be unsure if a 3 or a 7 or a 11 for example would divide equally.  I know a even number will divide by 2 and 5 divide into numbers ending with 0 and 5 but is their shortcut ways to find if a 3,7,11,13 etc will divide other than doing the full division?  ....I appreciate all the help

## #23 Re: Help Me ! » Help with this Prime factor sq root example » 2014-03-05 09:25:32

thanks bobbym, things are becoming clearer.  I'll feast on the MIF page after supper.....yum yum.

This is completely unrelated to my question but I'm curious, my son can do his UK GCSE higher maths exam at the end of year 11 and then additional maths (the cces board is changing the name this year to Further maths) at the end of year 12 so if all goes well he will have 2 GCSE maths and then begin 2 years of A-Level maths.  The additional/further qualification is like a bridge between GCSE and A-Level and is via the ccea exam board.  Does the English set-up have an equivalent "in between" type qualification.

Course Content

The course is divided into two sections, namely Pure Mathematics and Mechanics and Statistics.  Topics covered in each section are detailed below.

Pure Mathematics     Mechanics and Statistics
Algebra                     Linear Motion
Matrices                     Summarising Data
Trigonometry             Newton's Law
Logarithms                     Time Series
Differentiation             Equilibrium and Motion
Integration                     Bivariate Analysis
Moments of Forces
Probability

Does edexcel or aqa etc have similar?

## #24 Help Me ! » Help with this Prime factor sq root example » 2014-03-05 07:54:38

silverpuma
Replies: 6

Hi all,  I need some hand holding.  I just finished the GCSE foundation text book all 600 pages and after doing 3 full previous exams under exam conditions, timed etc I managed an average of 97% so I have a reasonably good grasp of the basics.

I just started the higher text book and just on page 16 after some pages on powers, roots primes, factors, multiples and then HCF and LCF (using prime factors) I arrived at examples 24 and 25 (see image of actual textbook page) it seemed to just jump up a level in understanding and I do not understand what the end of example 23 means: "Therefore 21 is the smallest value which 55125 can be multiplied by to give a cube number"

I understood all that came before this but I'm confused as to how this relates or builds upon what I have already learned......probably my 1.5 brain cells overheating....:-)  Where on the MIF site could I get some info that would help me understand this question and example 24 and especially 25 better.  I want to know why this works etc....... thanks and sorry for not being the sharpest chisel in the box!!!

## #25 Re: Help Me ! » On a multi-part question when do you round to significant figure? » 2014-02-02 02:46:50

Thanks Bob for the great answer and all makes perfect sense.....I suppose in maths like a lot of things in life there is a certain amount of "common" sense to be applied as well:-)