This question is incomplete, here is the complete question
What is the recursive formula for this geometric sequence 2, -10, 50, -250, .... ?
The recursive formula for this geometric sequence is:
= 2;
= (-5) • ![a_{n-1}](https://tex.z-dn.net/?f=a_%7Bn-1%7D)
Step-by-step explanation:
To find the recursive formula for a geometric sequence:
- Determine if the sequence is geometric (Do you multiply, or divide, the same amount from one term to the next?)
- Find the common ratio. (The number you multiply or divide.)
- Create a recursive formula by stating the first term, and then stating the formula to be the common ratio times the previous term.
The recursive formula is:
= first term;
= r •
, where
is the first term in the sequence
is the term before the nth term - r is the common ratio
∵ The geometric sequence is 2 , -10 , 50 , -250
∴
= 2
- To find r divide the 2nd term by the first term
∵ ![r=\frac{a_{2}}{a_{1}}](https://tex.z-dn.net/?f=r%3D%5Cfrac%7Ba_%7B2%7D%7D%7Ba_%7B1%7D%7D)
∴ ![r=\frac{-10}{2}=-5](https://tex.z-dn.net/?f=r%3D%5Cfrac%7B-10%7D%7B2%7D%3D-5)
- Substitute the values of
and r in the formula above
∴
= 2;
= (-5) • ![a_{n-1}](https://tex.z-dn.net/?f=a_%7Bn-1%7D)
The recursive formula for this geometric sequence is:
= 2;
= (-5) • ![a_{n-1}](https://tex.z-dn.net/?f=a_%7Bn-1%7D)
Learn more:
You can learn more about the geometric sequence in brainly.com/question/1522572
#LearnwithBrainly
The answer is 93 It’s 1209 divided by 13 not 13 divide by 1209 ;) hope this helps ! Because when we’re dividing the number get smaller and when we multiplying the number gets bigger , have a nice day !
Answer:
The answer is 4a
Step-by-step explanation:
1) Simplify 4a² + 12a² to 16a².
![\sqrt{ {16a}^{2} }](https://tex.z-dn.net/?f=%20%5Csqrt%7B%20%7B16a%7D%5E%7B2%7D%20%7D%20)
2) Use this rule:
![\sqrt{ab} = \sqrt{a} \sqrt{b}](https://tex.z-dn.net/?f=%20%5Csqrt%7Bab%7D%20%20%3D%20%20%5Csqrt%7Ba%7D%20%20%5Csqrt%7Bb%7D%20)
![\sqrt{16} \sqrt{ {a}^{2} }](https://tex.z-dn.net/?f=%20%5Csqrt%7B16%7D%20%20%5Csqrt%7B%20%7Ba%7D%5E%7B2%7D%20%7D%20)
3) Since 4 × 4 is 16, the square root of 16 is 4.
![4 \sqrt{ {a}^{2} }](https://tex.z-dn.net/?f=4%20%5Csqrt%7B%20%7Ba%7D%5E%7B2%7D%20%7D%20)
4) Simplify.
![4a](https://tex.z-dn.net/?f=4a)
<u>Therefor</u><u>,</u><u> </u><u>the</u><u> </u><u>answer</u><u> </u><u>is</u><u> </u><u>4a</u><u>.</u>
Answer:
628 inches cubed
Step-by-step explanation:
1. 3.14*10= 31.4
2. 31.4*20=628
628 in cubed