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    Hi guys,

    I am stuck on a question in my text book. It says "show that each algebraic fraction simplifies to the given expression." Here goes...

    2/x+1 + 5/x+2 =3 simplifies to 3x^3 +2x-3=0



    Basically I can solve these equations when the brackets are the numerators, but somehow I cannot solve them when the denominators need to be put into brackets (etc)

    Help :confused:
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    \frac{2}{x+1} + \frac{5}{x+2} = 0

    Is that the question?
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    (Original post by jayshah31)
    \frac{2}{x+1} + \frac{5}{x+2} = 0

    Is that the question?

    No it does not equal 0. It equals 3
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    find the comon denominator and then you should be able to show that it is equal to 3x^3 +2x-3=0... but dont forget to include the 3 in ur calculations
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    (Original post by Sophie Maywood)
    No it does not equal 0. It equals 3
    Ah. I see you've edited your original post Do the above, i.e. multiple everything by (x+1)(x+2)

    \frac{2(x+1)(x+2)}{x+1} + \frac{5(x+1)(x+2)}{x+2} = 3(x+1)(x+2)

    You can see you can cancel the fractions down and then expand those brackets, bring everything on one side (so it = 0), and you should be done :0
    Jay
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    I have crossed multiplyed and so far I have got 2(x+1)+5(x+1). Although how do you include the 3 in the calculation?
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    (Original post by Sophie Maywood)
    I have crossed multiplyed and so far I have got 2(x+1)+5(x+1). Although how do you include the 3 in the calculation?
    The first one should be 2(x+2). I edited my above post earlier, does that help now?
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    (Original post by Sophie Maywood)
    I have crossed multiplyed and so far I have got 2(x+1)+5(x+1). Although how do you include the 3 in the calculation?
    the comon denominator would be (x+1)(x+2)

    so if you subtract both sides by 3 teh u will get something like this :

    2(x+2)+5(x+1) -3(x+1)(x+2)
    (x+1)(x+2)

    but somehow i cant get to ur answer... are u sure that u typed in the right solution?
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    Here

    Spoiler:
    Show
    \\2x+4+5x+5-3(x^2+3x+2)=0\\

\\2x+4+5x+5-3x^2-9x-6=0\\

\\-3x^2-2x+3=0\\

\\3x^2+2x-3=0


    Might have typed it out wrong, but it works on paper.
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    giving full solutions is not ideal lol
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    (Original post by neomilan)
    giving full solutions is not ideal lol
    Hence the spoiler
 
 
 
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