Question 227034
I am supposed to use the laws of exponents to simplify:

{{{3^(3/4) *3^(3/8)}}}

Do I add the exponents...
Yes.

... to come up with 6/12,
No. {{{3/4+3/8}}} does not add up to 6/12. When you add fractions:<ol><li>the denominators must be the same before you add</li><li>you only add the numerators (<b>not</b> the denominators!)</li></ol>
{{{3/4+3/8}}}
The Lowest Common Denominator (LCD) here is 8. So we make the first fraction's denominator an 8 by multiplying it (and its numerator) by 2:
{{{(3/4)*(2/2)+3/8}}}
{{{6/8 + 3/8}}}
Now we can add:
{{{9/8}}}<br>
So {{{3^(3/4) *3^(3/8) =  3^(9/8)}}}