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# Maths logarithms help!! watch

1. Show that... log(base a)x^10 - 2log(base a)(x^3/4) = 4log(base a)(2x)
I can only get close to the answer but not the actual I don't think I fully understand the rules. Help would be appreciated my exams on Friday

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2. (Original post by Bethj1234)
Show that... log(base a)x^10 - 2log(base a)(x^3/4) = 4log(base a)(2x)
I can only get close to the answer but not the actual I don't think I fully understand the rules. Help would be appreciated my exams on Friday

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Do you know the following rules:

3. Yes I do! But I can't seem to apply them correctly to this question

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4. (Original post by Bethj1234)
Yes I do! But I can't seem to apply them correctly to this question

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First, try applying

to all the terms in the equation.
5. (Original post by Bethj1234)
Show that... log(base a)x^10 - 2log(base a)(x^3/4) = 4log(base a)(2x)
I can only get close to the answer but not the actual I don't think I fully understand the rules. Help would be appreciated my exams on Friday

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Wait. I think you have not typed the question correctly. Try substituting a value for x and LHS is not equal to RHS.
6. (Original post by Vorte)
Wait. I think you have not typed the question correctly. Try substituting a value for x and LHS is not equal to RHS.
You're supposed to find a value for x, obviously substituting a random x value isn't going to work...
7. I have done but I end up with log(base a)x^10 - log(base a)(x^6/16). It's he fraction I'm struggling with. I tried to make it not a fraction like you'd do with 1/x^2 becoming x^-2 but I'm not sure how to do it x on top.

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8. Does this work? I've probably done it wrong... ;L

Where did you find this question? Seems too complex to come up on Friday.
Attached Images

9. I think you may have read part of the question wrong, also it only says show that! Solving for x would be too nasty to come up. Here's the question

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Attached Images

10. Oh and the question is from june 2007 paper!

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11. Here you are:
Attached Images

12. (Original post by spiruel)
Here you are:
Why has the sign changed in the second step from "-" to a "+"
13. (Original post by Hi, How are you ?)
Why has the sign changed in the second step from "-" to a "+"
Log rule - the minus 2 has been put as a power for (x^3/4). You have you interpret minuses as plussing a minus... If that makes sense. Basically, revise log rules so you're sure.

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14. (Original post by Bethj1234)
I think you may have read part of the question wrong, also it only says show that! Solving for x would be too nasty to come up.

You didn't put brackets around the X^3/4 in your first post. That's why I misread it! You should have wrote it as (x^3)/4.

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15. Ah it's so simple thank you! I didn't realise if you had a coefficient infront of the x that you had to take the 4th root of 16 to make it 4loga(2x) thought it was just left as 16

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