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Core 3 - solving mod function - Help

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    Hello

    I've solved a mod equation (in image) and the next question is asking me to solve the same equation, involving logs:

    Name:  ImageUploadedByStudent Room1475415987.573474.jpg
Views: 28
Size:  40.5 KB

    (I'm stuck on the question I put a box around)

    I'm unsure how to use my previous answer (also in image) to answer this "hence" question


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    (Original post by Yusufff)
    Hello

    I've solved a mod equation (in image) and the next question is asking me to solve the same equation, involving logs:

    Name:  ImageUploadedByStudent Room1475415987.573474.jpg
Views: 28
Size:  40.5 KB

    (I'm stuck on the question I put a box around)

    I'm unsure how to use my previous answer (also in image) to answer this "hence" question


    Posted from TSR Mobile
    There is one key difference between  |x-9| \mathrm{and} |8^x - 9| - a substitution.. (you could swap out the x's for ys in your first answer if it helps.. for the second part, that is).
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    Ok so I'm up to here, would I take the natural log of everything to bring the power of x down?

    Name:  ImageUploadedByStudent Room1475416861.295135.jpg
Views: 26
Size:  62.2 KB


    (Original post by SeanFM)
    There is one key difference between  |x-9| \mathrm{and} |8^x - 9| - a substitution.. (you could swap out the x's for ys in your first answer if it helps.. for the second part, that is).



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    (Original post by Yusufff)
    Ok so I'm up to here, would I take the natural log of everything to bring the power of x down?

    Name:  ImageUploadedByStudent Room1475416861.295135.jpg
Views: 26
Size:  62.2 KB







    Posted from TSR Mobile
    Correctamundo so what does that give you?
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    (Original post by SeanFM)
    Correctamundo so what does that give you?
    I got 1/3 < x < 4/3 - which seems correct? If so thanks for your help
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    oml my head hurts
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    (Original post by Yusufff)
    I got 1/3 < x < 4/3 - which seems correct? If so thanks for your help
    Yes you'll see that fits into 2 < 8^x < 16 so it must be correct


    (Original post by mariam687)
    oml my head hurts

    I'm sure you'd ace it if you studied Maths
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    (Original post by SeanFM)
    Yes you'll see that fits into 2 < 8^x < 16 so it must be correct





    I'm sure you'd ace it if you studied Maths

    never, im only doing core maths for the sake of it ahaha
 
 
 
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