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    Just doing some revision - not sure what it means exactly with question 8 from paper c - c1 solomon papers.

    Figure one shows the graph of y = f(x)

    Write down the number of solutions that exist for the equation

    f(x) = 1

    f(x) = - x

    Answer in the mark scheme say 3 and 1 respectively but just not sure what the questions means....

    Must be something simply because its only worth two marks. ..
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    (Original post by christinajane)
    Just doing some revision - not sure what it means exactly with question 8 from paper c - c1 solomon papers.

    Figure one shows the graph of y = f(x)

    Write down the number of solutions that exist for the equation

    f(x) = 1

    f(x) = - x

    Answer in the mark scheme say 3 and 1 respectively but just not sure what the questions means....

    Must be something simply because its only worth two marks. ..
    You dont understand it, f(x)=1, whats f(x) and when it equals 1, how many solutions or points are there , and same for the next one, figure it out

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    Its a bit of a funny graph - doesn't give you f(x)

    It touches the x axis at -2 and 2 - so I thought f(x) = (x-2)(x+2) or (x-4)^2

    But the graph isn't a curve so its kinda throwing me little - hmmm
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    (Original post by christinajane)
    Its a bit of a funny graph - doesn't give you f(x)

    It touches the x axis at -2 and 2 - so I thought f(x) = (x-2)(x+2) or (x-4)^2

    But the graph isn't a curve so its kinda throwing me little - hmmm
    f(x) is the same as writing 'y', so all you do is draw the line f(x) = 1, otherwise known as y=1 on the graph they give you, then see how many times the line y=1 crosses the line drawn on the graph. This is the number of solutions you are looking for.

    Do the same for f(x) = -x
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    Ahhh yes!

    I thought I had to figure out f(x) by looking at the graph, because it doesn't give you f(x) - expand brackets etc equate it to one and find the solutions that way... over complicating matters
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    (Original post by christinajane)
    Ahhh yes!

    I thought I had to figure out f(x) by looking at the graph, because it doesn't give you f(x) - expand brackets etc equate it to one and find the solutions that way... over complicating matters
    That would work if they gave you an equation. This question is simpler too
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    is the equation of this graph not (X-2)(X-2)(X+2)?
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    you just need to sketch y = 1 and y = -x and see how many intersects do they have with original curve
 
 
 
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