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    Hello, could anyone help me with this question?
    How many solutions do these simultaneous equations have: y=x^3 and x-y=2.
    I rearranged the second equation to get y=x-2 then said that x^3=x-2 to find where they intersect.
    I then rearranged to get x^3-x+2=0 and tried to use factor theorem to find what x could be with no luck. Surely this would mean that they don't intersect but according to the answer book they intersect once. Could anyone help me please?
    Am I supposed to actually draw the two equations on a graph as this may not be accurate?
    Thanks
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    (Original post by etel)
    Hello, could anyone help me with this question?
    How many solutions do these simultaneous equations have: y=x^3 and x-y=2.
    I rearranged the second equation to get y=x-2 then said that x^3=x-2 to find where they intersect.
    I then rearranged to get x^3-x+2=0 and tried to use factor theorem to find what x could be with no luck. Surely this would mean that they don't intersect but according to the answer book they intersect once. Could anyone help me please?
    Am I supposed to actually draw the two equations on a graph as this may not be accurate?
    Thanks
    You can just draw a quick graph sketch to see how many solutions there are.

    The equation does have a single solution but it is not an integer.
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    (Original post by Notnek)
    You can just draw a quick graph sketch to see how many solutions there are.

    The equation does have a single solution but it is not an integer.
    Ah okay that makes sense. Thanks
 
 
 
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