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How To Simplify?? (6 marks!)

How do you do this question? Can you go through it step by step? :smile:

Thanks!

question b.png
Reply 1
Add the fractions

Multiply by the denominator

Cancel by 100

Collect on one side
Reply 2
Have you tried multiplying by 5x 5 - x and 5+x 5 + x ?
Reply 3
Original post by TenOfThem
Add the fractions

Multiply by the denominator

Cancel by 100

Collect on one side


Why add if it's minus?

Yeah I know cross multiplying :biggrin: It just doesn't get the correct answer :frown:

Ps can you help me on my other expression question? You're amazing at maths and with your explanation, I will def understand it! :h:
Original post by Groat
Have you tried multiplying by 5x 5 - x and 5+x 5 + x ?


Yes!
Reply 4
Original post by blueray
How do you do this question? Can you go through it step by step? :smile:

Thanks!

question b.png


Divide throughout by 100.

Get both fraction over a common denominator.

Example:

100x+1+100x1=10    10x+1+10x1=1    10(x1)(x+1)(x1)+10(x+1)(x1)(x+1)=10    10(x1)+10(x+1)(x+1)(x1)=1    10(x1)+10(x+1)=(x+1)(x1) \displaystyle \frac{100}{x+1} + \frac{100}{x-1} = 10 \implies \frac{10}{x+1} + \frac{10}{x-1} = 1 \\ \implies \frac{10(x-1)}{(x+1)(x-1)} + \frac{10(x+1)}{(x-1)(x+1)} = 10 \\ \implies \frac{10(x-1)+10(x+1)}{(x+1)(x-1)} = 1 \\ \implies 10(x-1)+10(x+1) = (x+1)(x-1)
Reply 5
Original post by blueray
Why add if it's minus?

Yeah I know cross multiplying :biggrin: It just doesn't get the correct answer :frown:

Ps can you help me on my other expression question? You're amazing at maths and with your explanation, I will def understand it! :h:


Yes!


Where have you got so far? Which part of your working are you stuck at?
Reply 6
Original post by blueray
Why add if it's minus?




Well ... subtract then ... but that is just adding a negative so my post holds
Reply 7
Original post by tyre
...


Please don't post full solutions. Click here for guidelines to posting in the maths forum.
Reply 8
I have learnt how to do it thanks! :biggrin: I just cross multiply it! I accidently put the x and 5 wrong way, so I was mixed up. Sorry!

Original post by nuodai
Please don't post full solutions. Click here for guidelines to posting in the maths forum.


No please, it's fine. In my case I really do need the solution, it doesn't matter, because I have the mark scheme, I just need clarification on it. So please don't remove next time! Thanks!
Reply 9
Original post by TenOfThem
Add the fractions

Multiply by the denominator

Cancel by 100

Collect on one side



Original post by Groat
Have you tried multiplying by 5x 5 - x and 5+x 5 + x ?



Original post by raheem94
Divide throughout by 100.

Get both fraction over a common denominator.

Example:

100x+1+100x1=10    10x+1+10x1=1    10(x1)(x+1)(x1)+10(x+1)(x1)(x+1)=10    10(x1)+10(x+1)(x+1)(x1)=1    10(x1)+10(x+1)=(x+1)(x1) \displaystyle \frac{100}{x+1} + \frac{100}{x-1} = 10 \implies \frac{10}{x+1} + \frac{10}{x-1} = 1 \\ \implies \frac{10(x-1)}{(x+1)(x-1)} + \frac{10(x+1)}{(x-1)(x+1)} = 10 \\ \implies \frac{10(x-1)+10(x+1)}{(x+1)(x-1)} = 1 \\ \implies 10(x-1)+10(x+1) = (x+1)(x-1)



Original post by tyre
(Removed by moderator.)



Original post by nuodai
Please don't post full solutions. Click here for guidelines to posting in the maths forum.


Can anyone of you help me on this question?

http://www.thestudentroom.co.uk/showthread.php?t=1991188

Thank you! :smile:
Reply 10
Original post by blueray
No please, it's fine. In my case I really do need the solution, it doesn't matter, because I have the mark scheme, I just need clarification on it. So please don't remove next time! Thanks!

Original post by blueray
Can anyone of you help me on this question?

http://www.thestudentroom.co.uk/showthread.php?t=1991188

Thank you! :smile:


All you have to do is follow raheem94's solution line-for-line, but changing the numbers as appropriate, and you'll get your answer. If you're still stuck, show your working and we'll help you get there. It won't take much work to do this, but you'll learn much more from it than you would from copying out a solution line-for-line without having to think about it at all.
(edited 11 years ago)
Reply 11
Original post by nuodai
Please don't post full solutions. Click here for guidelines to posting in the maths forum.


Sorry for you getting a neg rep for abiding with the laws, the rep system is flawed in my opinion.
Reply 12
Original post by raheem94
Sorry for you getting a neg rep for abiding with the laws, the rep system is flawed in my opinion.


People are welcome to give me neg rep if they think I've done something wrong. (If anything, rep whether pos or neg will help me work out whether or not I'm screwing up this newfangled 'moderator' thing or not!)

But in this case I'm quite sure of my position: the full solution, albeit correct, was a cop-out for the OP and undermined the effort that other users had put into trying to help the OP actually develop maths skills rather than copying-out skills.
Reply 13
Original post by nuodai
People are welcome to give me neg rep if they think I've done something wrong. (If anything, rep whether pos or neg will help me work out whether or not I'm screwing up this newfangled 'moderator' thing or not!)


But your neg rep was undeserved. It won't allow me to +rep you to cancel that out.

By the way, congrats for becoming a moderator!
:congrats:

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