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1. I've been trying to do this question and I have no idea how to even begin. It makes no sense to me:

Given that loga(x^2) = 3 show without the use of a calculator that

loga(x^2) + ln(x^3)+6loga(x) = (17/3)ln(x)

2. (Original post by HelloGoodbye)
I've been trying to do this question and I have no idea how to even begin. It makes no sense to me:

Given that loga(x^2) = 3 show without the use of a calculator that

loga(x^2) + ln(x^3)+6loga(x) = 17/3ln(x)

Log(x^2)=2log(x)

you will also need to use the change of base rule
3. (Original post by HelloGoodbye)
thanks!

so I've changed it to 2loga(x) + 3lnx + 6loga(x) + (17/3)lnx

what base do I need to change? loga?
You should not have the (17/3)lnx

That is what you are trying to get

So the rest needs to be in ln
4. (Original post by TenOfThem)
You should not have the (17/3)lnx

That is what you are trying to get

So the rest needs to be in ln
ok so I got 17lnx by doing this:

2loga(x) + 3lnx + 6loga(x)

2(lnx/lna) + 3lnx + 6(lnx/lna)

I multiplied it by lna to get 2lnx + lna3lnx +6lnx

2lnx + 9lnx + 6lnx = 17lnx

I don't know where I went wrong, i'm supposed to get 17/3lnx
5. (Original post by HelloGoodbye)
ok so I got 17lnx by doing this:

2loga(x) + 3lnx + 6loga(x)

2(lnx/lna) + 3lnx + 6(lnx/lna)

I multiplied it by lna to get 2lnx + lna3lnx +6lnx

2lnx + 9lnx + 6lnx = 17lnx

I don't know where I went wrong, i'm supposed to get 17/3lnx
You have 3lnalnx and then you change that to 9lna ... Why

From the first line

2logx + 3lnx + 6logx

You can use the fact that logx = 1.5

Do you have a picture of the question as it does not seem to work
6. (Original post by TenOfThem)
You have 3lnalnx and then you change that to 9lna ... Why

From the first line

2logx + 3lnx + 6logx

You can use the fact that logx = 1.5

Do you have a picture of the question as it does not seem to work
Am pretty sure the question as stated is not true. I did assume logax was though.
7. (Original post by joostan)
Am pretty sure the question as stated is not true. I did assume logax was though.
Ditto
8. (Original post by HelloGoodbye)
I've been trying to do this question and I have no idea how to even begin. It makes no sense to me:

Given that loga(x^2) = 3 show without the use of a calculator that

loga(x^2) + ln(x^3)+6loga(x) = (17/3)ln(x)

As the others have said, this question doesn't seem to work as stated!

Can you provide a screenshot or image of the question?

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Updated: January 15, 2015
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