no cal multiple choice

Given Log 6 = x Log 8 = ydetermine an expression for log3 interms of x and y.

a: x/3 - y

b: x-y/3

c: y/3-x

d y-x/3

Don't understand how to turn log 3 into log 6 and log8.. help

ThankYou

Printable View

- December 7th 2009, 08:44 PMhovermetdetermine an expression for log3 interms of x and y
no cal multiple choice

Given Log 6 = x Log 8 = y**determine an expression for log3 interms of x and y**.

a: x/3 - y

b: x-y/3

c: y/3-x

d y-x/3

Don't understand how to turn log 3 into log 6 and log8.. help

ThankYou - December 7th 2009, 08:57 PMqmech
remember log(xy) = log(x) + log(y). So

log 6 = log (2*3) = log 2 + log 3.

Also log 8 = log 2*2*2 = log 2 + log 2 + log 2 = 3log2.

Can you proceed? - December 7th 2009, 09:27 PMhovermet
Sorry.. i can't proceed.

If log2 + log3

log2 + x

3log2 = log2^3

..ah..>.< - December 7th 2009, 09:50 PMProve It
Start with the fact that

.

Call this Equation 1.

Also, remember that

.

Substitute this back into Equation 1.

.

So none of your possibilities are correct... - December 8th 2009, 04:20 AMSoroban
Hello, hovermet!

Quote:

Given: .

Determine an expression for in terms of and

. .

Note that: .

So we have: .

- December 8th 2009, 01:38 PMhovermet
Thanks guys.. it seems like i forgot an AND between log 6 = x Log 8 = y ^^;

In fact, i done the log test pretty well today with the understanding of the mistaken question Thanks^^