A formula is recursive if it expresses the term
in terms of the previous one(s) 
In this case, every term is 7 more than the previous one, so the formula for
will only involve
:

In fact, this formula is simply saying: for every index
, the term with that index is 7 more than the term before.
Also, we have to specify the starting point (otherwise we would go backwards indefinitely), so the complete recursive formula is

which means: start with 2 and generate every other term by adding 7 to the previous one.
Answer:
x = 22
Step-by-step explanation:
22 x 4 = 88
<u>Answer:</u>
<u>Step-by-step explanation:</u>
<u>Let's find 'a' using Pythagoras theorem.</u>
- => 4² = 2² + a²
- => 16 = 4 + a²
- => 12 = a²
- => a = √12
- => a = √2 x 2 x 3
- => a = 2√3
- => a = 2 x √3
- => a = 2 x 1.732
- => a = 3.464 = 3.5 (Estimated)
Hoped this helped.

Looks like you meant to write (p/q)³ if so it's power of a quotient
According to the fundemintal counting princable the answer is 18.