Answer:
The rule would be 4ⁿ
4²¹
Step-by-step explanation:
This is a geometric sequence, the terms are all powers of 4.
The rule here would be 4ⁿ
To find the 21st term, we simply substitute 21 for n in our rule. So:
= 4²¹
Leaving in index form is fine as the expanded number is very large
