factorising help
Maths and statistics discussion, revision, exam and homework help.
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Re: factorising helpYou have two terms: 6y(x+3y) and 9(x+3y)^2. To factorise, you need to look for common factors in both terms. 3 and (x+3y) are common factors so you can take them outside the expression. So you'll have this:
3(x+3y)( ...... )
Can your work out what will go inside the brackets? -
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Re: factorising helpNo the way I have been taught is to expand the brackets and then do it(Original post by notnek)
You have two terms: 6y(x+3y) and 9(x+3y)^2. To factorise, you need to look for common factors in both terms. 3 and (x+3y) are common factors so you can take them outside the expression. So you'll have this:
3(x+3y)( ...... )
Can your work out what will go inside the brackets? -
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Re: factorising helpHave fun wasting your time.(Original post by zed963)
No the way I have been taught is to expand the brackets and then do it -
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Re: factorising helpSometimes it is useful to expand and then factorise but not in this case. Expanding this expression will make it harder to factorise and that could be the reason why you're having trouble with the question.(Original post by zed963)
No the way I have been taught is to expand the brackets and then do it
I'm pretty sure that your teacher would expect you to factorise using the method I showed in my last post. -
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Re: factorising helpYou appear to have been taught 'wrong'. ALWAYS try and factorise by using the highest common factor. In this case the obvious factors to 'go outside' are 3(x+3y)(Original post by zed963)
No the way I have been taught is to expand the brackets and then do it -
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Re: factorising helpWow you have a retarded teacher.(Original post by zed963)
No the way I have been taught is to expand the brackets and then do it
Take a factor of (x+3y) from every term so you get (x+3y)(6y+9(x+3y))
Expand within the second bracket and collect the terms. Another factor can be taken out and that is 3, from the second bracket only.Last edited by uttamo; 21-04-2012 at 18:31. Reason: little mistake -
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Re: factorising helpI would not be so quick to criticise the teacher in this case(Original post by uttamo)
Wow you have a retarded teacher.
Have you spoken to your teacher since we tried to help you with these
Do not suggest that you have not been shown how to factorise these as we spent A LOT of time on them with you last weekend
When you still did not understand we said that you should seek personal help at school
So I ask again ... HAVE YOU?
Before people waste too much time
http://www.thestudentroom.co.uk/show....php?t=1969289Last edited by TenOfThem; 21-04-2012 at 18:59. -
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Re: factorising helpI asked about the algebraic fraction one(Original post by TenOfThem)
I would not be so quick to criticise the teacher in this case
Have you spoken to your teacher since we tried to help you with these
Do not suggest that you have not been shown how to factorise these as we spent A LOT of time on them with you last weekend
When you still did not understand we said that you should seek personal help at school
So I ask again ... HAVE YOU?
Before people waste too much time
http://www.thestudentroom.co.uk/show....php?t=1969289 -
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Re: factorising helpBut not about this? ... in spite of the fact that you asked and asked last week but clearly did not "get it"(Original post by zed963)
I asked about the algebraic fraction one -
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Re: factorising helpI will ask(Original post by TenOfThem)
But not about this? ... in spite of the fact that you asked and asked last week but clearly did not "get it" -
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Re: factorising helpGood(Original post by zed963)
I will ask
You need someone to sit down with you on this -
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Re: factorising helpHere is one way that might help. Let A = x + 3y(Original post by zed963)
I will askLast edited by steve2005; 21-04-2012 at 21:59. -
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Re: factorising helpAwesome you made me understand.(Original post by steve2005)
Here is one way that might help. Let A = x + 3y
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Re: factorising helpYeah you're right lol I take it back(Original post by TenOfThem)
I would not be so quick to criticise the teacher in this case -
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Re: factorising helpI would use the difference of 2 squares(Original post by zed963)
So how would I do 50(2x+1)^2-18(1-x)^2
Spoiler:Show
![50(2x+1)^2 - 18(x-1)^2 = 2[5(2x+1) + 3(x-1)][5(2x+1) - 3(x-1)]](http://www.thestudentroom.co.uk/latexrender/pictures/8a/8a69dbc178cfa1c20b3719a4515dc222.png "50(2x+1)^2 - 18(x-1)^2 = 2[5(2x+1) + 3(x-1)][5(2x+1) - 3(x-1)]")
Spoiler:Show2(13x+2)(7x+8)
It might be easier for you to expand and simplifyLast edited by TenOfThem; 22-04-2012 at 16:46. -
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Re: factorising help? I didn't understand what u meant(Original post by TenOfThem)
I would use the difference of 2 squares
It might be easier for you to expand and simplify -
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Re: factorising helpThat's why she suggested that YOU should expand the brackets first.(Original post by zed963)
? I didn't understand what u meant
