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    Name:  cccccc.png
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    It is that ... but you need to actually simplify

    If you had not multiplied the brackets in the denominator you would have seen how to cancel
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    you can simplify it more
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    (Original post by Albino)
    you can simplify it more
    how?

    do I need to factorize?
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    (Original post by madfish)
    how?

    do I need to factorize?
    mhm dont expand brackets until the end because its easier to spot cancelling
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    (Original post by TenOfThem)
    It is that ... but you need to actually simplify

    If you had not multiplied the brackets in the denominator you would have seen how to cancel
    (Original post by madfish)
    how?

    do I need to factorize?
    Dropped a negative. Those aren't equivalent.

    \dfrac{1}{x+3} - \dfrac{1}{x-2} = \dfrac{(x-2)-(x+3)}{(x+3)(x-2)}
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    (Original post by Indeterminate)
    Dropped a negative. Those aren't equivalent.

    \dfrac{1}{x+3} - \dfrac{1}{x-2} = \dfrac{(x-2)-(x+3)}{(x+3)(x-2)}
    wait.. so it would simplify to "-1"?
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    (Original post by madfish)
    wait.. so it would simplify to "-1"?
    No, the numerator simplifies to

    (x-2) - (x+3) = x-2-x-3 = -2-3 = -5
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    (Original post by Noble.)
    No, the numerator simplifies to

    (x-2) - (x+3) = x-2-x-3 = -2-3 = -5
    I thought the (x+3) and (x-2) cancel each other?
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    (Original post by madfish)
    I thought the (x+3) and (x-2) cancel each other?
    Cancel each other how?
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    (Original post by Noble.)
    Cancel each other how?
    there is one of each in both the numerator and denominator?
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    (Original post by madfish)
    there is one of each in both the numerator and denominator?
    Ok, let's assume what you're saying is true - that:

    \dfrac{1}{x+3} - \dfrac{1}{x-2} = \dfrac{(x-2)-(x+3)}{(x+3)(x-2)} = -1

    Then this implies two things, firstly it implies that no matter what values of x you insert, you always get -1 and secondly it implies that for any two values of x you get the same answer. Neither of which is true. Try x=0 - do you get -1?
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    (Original post by Indeterminate)
    Dropped a negative.
    must be asleep
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    (Original post by madfish)
    Name:  cccccc.png
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    i was think is going to be biology question because i knowing you say is difficult?
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    (Original post by Mullah.S)
    i was think is going to be biology question because i knowing you say is difficult?
    Yea, memorizing that amount of information can be quite challenging at times
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    (Original post by madfish)
    Yea, memorizing that amount of information can be quite challenging at times
    So, made any progress from where we were last?

    You did everything correct apart from dropping the negative, so you can state the correct answer immediately and simplify. Hint: leave the denominator in factorised form.
 
 
 
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