Expert: Richard J. Raridon - 3/1/2008

Question
I have two . (1)How do you multiply exponents when the base is the same but one exponent is positive and the other negative. such as 7 to the second power times 7 to the -5 power? My teacher has the answer as 1 over 343 and I am not getting it?
(2)How do you divide square roots, example 6 over the square root of 2. the answer is 3 square root 2?

My test is next Wednesday March 5th

THank you Darlene  

Answer
(1) you add the exponents so 7^2 times 7^-5 = 7^-3 or 1/7^3 which is
1/343
You can write square roots as x^1/2 or 2^1/2
(2) You don't divide them.  You multiply them by something to get rid of any radical signs in the denominator.  In this case you multiply top and bottom by 2^1/2 which will give you 3(2^1/2)