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    I've just been given a question:

    Simplify the following in the form a + b?c where a, b and c are intergers:

    a) (3+?2)^2

    b) (2?3+4)(2-?3)

    c) 2/?3-1

    No need to actually give me the answers, just tell me how to simplify them

    Must have been sleeping/generally not paying attention when I was supposed to learn these :rolleyes: Or it could be that these questions were thrown in just to be evil and I was never taught them at all! :eek:

    (probably the former )

    Thanks in advance.
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    OK, I don't know why my square root signs are showing up as question marks, sorry.
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    (Original post by james-brown28)
    I've just been given a question:

    Simplify the following in the form a + b?c where a, b and c are intergers:

    a) (3+?2)^2

    b) (2?3+4)(2-?3)

    c) 2/?3-1

    No need to actually give me the answers, just tell me how to simplify them

    Must have been sleeping/generally not paying attention when I was supposed to learn these :rolleyes: Or it could be that these questions were thrown in just to be evil and I was never taught them at all! :eek:

    (probably the former )

    Thanks in advance.
    For a and b, just expand the brackets and collect like terms. c is already in that form ( or it could be written -1+2rt3)
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    (Original post by james-brown28)
    I've just been given a question:

    Simplify the following in the form a + b?c where a, b and c are intergers:

    a) (3+?2)^2

    b) (2?3+4)(2-?3)

    c) 2/?3-1

    No need to actually give me the answers, just tell me how to simplify them

    Must have been sleeping/generally not paying attention when I was supposed to learn these :rolleyes: Or it could be that these questions were thrown in just to be evil and I was never taught them at all! :eek:

    (probably the former )

    Thanks in advance.
    Use this: (a+b) x (c+d) = ac+ad+bc+bd

    Also use 1/sqr(3) = sqr(3)/3

    where sqr is square root.

    So (3+sqr(2))^2 = 9 + 2 + 6sqr(2) = 11 + 6sqr(2)
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    a) Use the fact that

    (p+\sqrt{q})^2 = (p+\sqrt{q})(p+\sqrt{q})
    (p+\sqrt{q})(p+\sqrt{q}) = p^2 + 2p\sqrt{q} + q

    b) Use similar ideas to above.

    c) Rationalise the denominator.

    \frac{a+\sqrt{b}}{c-\sqrt{d}} \times \frac{c+\sqrt{d}}{c+\sqrt{d}} = \frac{(a+\sqrt{b})(c+\sqrt{d})}{  (c-\sqrt{d})(c+\sqrt{d})}
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    (Original post by indifferencepersonified)
    For a and b, just expand the brackets and collect like terms. c is already in that form ( or it could be written -1+2rt3)
    No, the sqr ia at the bottom in c

    2/?3-1 is in fact -1 + 2/3 sqr(3)
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    (Original post by Ienjoylife)
    No, the sqr ia at the bottom in c

    2/?3-1 is in fact -1 + 2/3 sqr(3)
    No.

    \frac{2}{\sqrt{3}-1} \neq -1 + \frac{2}{3} \sqrt{3}
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    (Original post by Ienjoylife)
    No, the sqr ia at the bottom in c

    2/?3-1 is in fact -1 + 2/3 sqr(3)
    I misread that, I didn't see the '/'
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    (Original post by Noble.)
    No.

    \frac{2}{\sqrt{3}-1} \neq -1 + \frac{2}{3} \sqrt{3}
    errmm excuse me but there were no brackets in the original stem (c). It showed as \frac{2}{\sqrt{3}}-1
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    (Original post by Ienjoylife)
    errmm excuse me but there were no brackets in the original stem (c). It showed as \frac{2}{\sqrt{3}}-1
    I'm fairly sure the question was a bog-standard rationalise the denominator question. Kind of pointless for \frac{2}{\sqrt{3}}-1
 
 
 
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