# Logarithms Homework Help!

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Hello! New to this so not too sure how to work it was just wondering if any of you clever students out there could help me with this question:

Solve for x, round your answers to 2 dec places,

ln(x) + ln(4x) - ln(2x) = 1

Hope someone can help! Thank you!

Beth.

Solve for x, round your answers to 2 dec places,

ln(x) + ln(4x) - ln(2x) = 1

Hope someone can help! Thank you!

Beth.

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#2

Use your laws of logs to get the left hand side as a single logarithm:

loga + logb = log(ab)

loga - logb = log(a/b)

Posted from TSR Mobile

loga + logb = log(ab)

loga - logb = log(a/b)

Posted from TSR Mobile

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#4

(Original post by

Hello! New to this so not too sure how to work it was just wondering if any of you clever students out there could help me with this question:

Solve for x, round your answers to 2 dec places,

ln(x) + ln(4x) - ln(2x) = 1

Hope someone can help! Thank you!

Beth.

**BethArkless**)Hello! New to this so not too sure how to work it was just wondering if any of you clever students out there could help me with this question:

Solve for x, round your answers to 2 dec places,

ln(x) + ln(4x) - ln(2x) = 1

Hope someone can help! Thank you!

Beth.

(Original post by

Use your laws of logs to get the left hand side as a single logarithm:

loga + logb = log(ab)

loga - logb = log(a/b)

Posted from TSR Mobile

**Cyclohexane**)Use your laws of logs to get the left hand side as a single logarithm:

loga + logb = log(ab)

loga - logb = log(a/b)

Posted from TSR Mobile

Use the rules quoted to get ln((4x^2)/2x)=1

Simplify inside the brackets to get ln(2x)=1

Now for the part that you either undersrstand or don't, if you don't understand just accept this as maths magic and learn where it applies: You are using ln, the natural log of the number e

Therefore ln(e)=1

And e*ln(x)=x

Therefore if we multiply both sides by e we get:

2x=e

Therefore our answer is x=(1/2)e

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#5

(Original post by

Simples.

Use the rules quoted to get ln((4x^2)/2x)=1

Simplify inside the brackets to get ln(2x)=1

Now for the part that you either undersrstand or don't, if you don't understand just accept this as maths magic and learn where it applies: You are using ln, the natural log of the number e

Therefore ln(e)=1

And e*ln(x)=x

Therefore if we multiply both sides by e we get:

2x=e

Therefore our answer is x=(1/2)e

**Ollie113**)Simples.

Use the rules quoted to get ln((4x^2)/2x)=1

Simplify inside the brackets to get ln(2x)=1

Now for the part that you either undersrstand or don't, if you don't understand just accept this as maths magic and learn where it applies: You are using ln, the natural log of the number e

Therefore ln(e)=1

And e*ln(x)=x

Therefore if we multiply both sides by e we get:

2x=e

Therefore our answer is x=(1/2)e

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#6

(Original post by

I swear that's like C3/C4 level? all the OP has to do is start by using the multiplication law and then the division law to express it is a single logarithm

**Robbie242**)I swear that's like C3/C4 level? all the OP has to do is start by using the multiplication law and then the division law to express it is a single logarithm

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Would you not just bring ln to the other side to make it 2x=e^1 ? And then just divide tat answer by 2 to find x?

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#8

(Original post by

Would you not just bring ln to the other side to make it 2x=e^1 ? And then just divide tat answer by 2 to find x?

**BethArkless**)Would you not just bring ln to the other side to make it 2x=e^1 ? And then just divide tat answer by 2 to find x?

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