SOLUTION: Write log a sqrt(6) , in terms of "p" and "q" , if log a 2 = p and log a 3 = q Thank you for taking the time to help me out.

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: Write log a sqrt(6) , in terms of "p" and "q" , if log a 2 = p and log a 3 = q Thank you for taking the time to help me out.       Log On


   



Question 354508: Write log a sqrt(6) , in terms of "p" and "q" , if log a 2 = p and log a 3 = q
Thank you for taking the time to help me out.

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
log%28a%2C+%282%29%29+=+p
log%28a%2C+%283%29%29+=+q
log%28a%2C+%28sqrt%286%29%29%29
The first key to this problem is to know that square roots can be expressed using fractional exponents: sqrt%28x%29+=+x%5E%281%2F2%29. So we can rewrite your expression using an exponent of 1/2:
log%28a%2C+%286%5E%281%2F2%29%29%29%29
Now we can start using the properties of logarithms:
  • log%28n%2C+%28x%2Ay%29%29+=+log%28n%2C+%28x%29%29+%2B+log%28n%2C+%28y%29%29
  • log%28n%2C+%28x%2Fy%29%29+=+log%28n%2C+%28x%29%29+-+log%28n%2C+%28y%29%29
  • log%28n%2C+%28x%5Ey%29%29+=+y%2Alog%28n%2C+%28x%29%29

We can use the third property to remove the exponent:
%281%2F2%29%2Alog%28a%2C+%286%29%29
Now we need to change the argument from a six to something in terms of 2's and/or 3's. It should be obvious that 6 = 2*3 so now we have:
%281%2F2%29%2Alog%28a%2C+%282%2A3%29%29
In this form we can use the first property to separate the log into two logs:
%281%2F2%29%2A%28log%28a%2C+%282%29%29+%2B+log%28a%2C+%283%29%29%29
Next we can subsitute in for the two logs:
%281%2F2%29%2A%28p+%2B+q%29
And finally we can use the Distributive Property:
%281%2F2%29%2Ap+%2B+%281%2F2%29%2Aq