206k views
2 votes
I need a better step by step on how to get the answer instead of just “calculate 9 to the power of -5/2 and get 1/243

User Chantey
by
4.0k points

1 Answer

6 votes

The question ask to evaluate the expression:


9^{-(5)/(2)}

Step 1: Factor the number


9=3^2

Therefore, the expression becomes:


\Rightarrow(3^2)^{-(5)/(2)}

Step 2: Apply the exponent rule given to be


(x^a)^b=x^(a* b)

Therefore, we have:


\Rightarrow(3^2)^{-(5)/(2)}=3^{2*-(5)/(2)}=3^(-5)

Step 3: Apply the exponent rule given to be


x^(-a)=(1)/(x^a)

Therefore, the expression becomes:


3^(-5)=(1)/(3^5)

Step 4: Calculate


3^5=243

Therefore, we have


(1)/(3^5)=(1)/(243)

ANSWER


9^{-(5)/(2)}=(1)/(243)

User Shizam
by
4.8k points