SOLUTION: Can you please help me simplify {{{3a^-2}}} and {{{(x^2y^-3)^2}}} please i really need help i have a test tomarrow and i still don't understand this stuff.

Algebra ->  Exponents-negative-and-fractional -> SOLUTION: Can you please help me simplify {{{3a^-2}}} and {{{(x^2y^-3)^2}}} please i really need help i have a test tomarrow and i still don't understand this stuff.      Log On


   

Question 198756: Can you please help me simplify 3a%5E-2 and %28x%5E2y%5E-3%29%5E2 please i really need help i have a test tomarrow and i still don't understand this stuff.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Recall that x%5E%28-2%29=1%2Fx%5E2. If you have a negative exponent, then you simply flip the fraction to make it positive.

So 3a%5E%28-2%29=3%281%2Fa%5E2%29=3%2Fa%5E2


which means that 3a%5E%28-2%29=3%2Fa%5E2


------------------------------------------------

Also, we'll use the identity %28x%5Ey%29%5Ez=x%5E%28y%2Az%29


%28x%5E2y%5E%28-3%29%29%5E2 Start with the given expression.


x%5E%282%2A2%29y%5E%28%28-3%29%2A%282%29%29 Use the identity given above to multiply the outer exponent with EVERY exponent inside the parenthesis.


x%5E%284%29y%5E%28-6%29 Multiply


x%5E%284%29%281%2Fy%5E6%29 Now flip the fraction to make the exponent positive


x%5E4%2Fy%5E6 Multiply


So %28x%5E2y%5E%28-3%29%29%5E2=x%5E4%2Fy%5E6