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    Hi
    I haven't understood how to do these types of questions, could someone give a step by step answer please? thanks
    "Express (2- √3)² in the form b + c√3, where b and c are integers to be found"
    Thanks so much
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    (Original post by eliwats)
    Hi
    I haven't understood how to do these types of questions, could someone give a step by step answer please? thanks
    "Express (2- √3)² in the form b + c√3, where b and c are integers to be found"
    Thanks so much
    Expand the brackets
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    Consider this:

    (2- √3)² is the same as (2- √3)(2- √3)

    From there, you just use FOIL to multiply out the brackets. And don't worry, you will end up with an answer in the form b + c√3 (unless you're using a calculator, in which case, you'd end up being kicked out of the C1 exam, anyway .)
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    (Original post by Crack Cupcake)
    Consider this:

    (2- √3)² is the same as (2- √3)(2- √3)

    From there, you just use FOIL to multiply out the brackets. And don't worry, you will end up with an answer in the form b + c√3 (unless you're using a calculator, in which case, you'd end up being kicked out of the C1 exam, anyway .)
    hi
    I have expanded the brackets, that wasn't a problem but now I have 7-4√3, yet the question is asking for an answer as b + c√3. How do I proceed?
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    (Original post by eliwats)
    hi
    I have expanded the brackets, that wasn't a problem but now I have 7-4√3, yet the question is asking for an answer as b + c√3. How do I proceed?
    That's the right answer, since b and c can be either positive or negative, unless the question specifically states otherwise, so in this case, c is -4.
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    (Original post by Crack Cupcake)
    That's the right answer, since b and c can be either positive or negative, unless the question specifically states otherwise, so in this case, c is -4.
    wow that makes sense.
    Thanks so much!!!
 
 
 
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