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Core 3 - solving mod function - Help

Hello

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

ImageUploadedByStudent Room1475415987.573474.jpg

(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
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:

ImageUploadedByStudent Room1475415987.573474.jpg

(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∣and∣8x−9∣ |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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Avatar for Yusufff
Yusufff
OP
10
Ok so I'm up to here, would I take the natural log of everything to bring the power of x down?

ImageUploadedByStudent Room1475416861.295135.jpg


Original post by SeanFM
There is one key difference between ∣x−9∣and∣8x−9∣ |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).





Posted from TSR Mobile
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?

ImageUploadedByStudent Room1475416861.295135.jpg







Posted from TSR Mobile


Correctamundo :h: so what does that give you?
Reply 4
Avatar for Yusufff
Yusufff
OP
10
Original post by SeanFM
Correctamundo :h: so what does that give you?


I got 1/3 < x < 4/3 - which seems correct? If so thanks for your help :smile:
oml my head hurts
Original post by Yusufff
I got 1/3 < x < 4/3 - which seems correct? If so thanks for your help :smile:


Yes :h: 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 :wink:
Original post by SeanFM
Yes :h: 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 :wink:



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

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