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    I'm struggling with this question.
    I've done part i)
    i) sketch the curve 2 times 3^x, stating the co-ordinates of any intersections with the axes.
    ii) the curve y=2*3^x intersects the curve y=8^x at the point P. Show that the x co-ordinate of P may be written as 1/(3-log2 3)
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    So the graphs intersect, so you equate them:

    

2 \times \ 3^x = 8^x

    in what they want you to show, they have a  log_2 , so you would take the  log_2
    of both sides.

    Use log rules and simply, rearrange to get it into that form
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    (Original post by Nooglepop)
    I'm struggling with this question.
    I've done part i)
    i) sketch the curve 2 times 3^x, stating the co-ordinates of any intersections with the axes.
    ii) the curve y=2*3^x intersects the curve y=8^x at the point P. Show that the x co-ordinate of P may be written as 1/(3-log2 3)
    Equate the two curves, and then take logs The logarithm in the answer is base two, that tells you that you need to take logs base 2. Remember to use the laws of logs throughout the answer
    log(ab) = log(a) + log(b) in particular
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    (Original post by Nooglepop)
    I'm struggling with this question.
    I've done part i)
    i) sketch the curve 2 times 3^x, stating the co-ordinates of any intersections with the axes.
    ii) the curve y=2*3^x intersects the curve y=8^x at the point P. Show that the x co-ordinate of P may be written as 1/(3-log2 3)
    2\cdot 3^x = 8^x =2^{3x} \Rightarrow 3^x=2^{3x-1} and now take log base 2 of both sides then rearrange.
 
 
 
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