log

[ocgirl83]

ln (5+4x) - ln (3+x) = ln3

 

[stapel]

This one works just like the other ones you've posted, and by the same reasoning and rules that the other tutors have explained and demonstrated:

1) Apply log rules to combine terms to get "log(something) = log(something else)".

2) Set "something" equal to "something else".

3) Solve.

Please reply showing how far you have gotten and where you are stuck. Please be specific. Thank you.

Eliz.

 

[ocgirl83]

i get that it would be (5+4x/ 3+x) = 3 but i dont know what the quotient would be, that is where i am having problems.

 

[stapel]

i get that it would be (5+4x/ 3+x) = 3...

So you have:

. . . . .\(\displaystyle \Large{\frac{5\mbox{ }+\mbox{ }4x}{3\mbox{ }+\mbox{ }x}=\frac{3}{1}}\)

(I'm pretty sure that's what you meant, anyway.)

So cross-multiply as usual:

. . . . .\(\displaystyle \large{1(5\mbox{ }+\mbox{ }4x)\mbox{ }=\mbox{ }3(3\mbox{ }+\mbox{ }x)}\)

Then solve the linear equation by the usual methods.

Remember to check your solution in the original equation, to make sure it works.

Eliz.