Answered

Explore Westonci.ca, the leading Q&A site where experts provide accurate and helpful answers to all your questions. Get quick and reliable solutions to your questions from a community of seasoned experts on our user-friendly platform. Our platform offers a seamless experience for finding reliable answers from a network of knowledgeable professionals.

Suppose a term of a geometric sequence is a4 = 121.5 and the common ratio is 3. Write the formula for this sequence in the form an = a1 ⋅ rn−1. Explain how you arrived at your answer.

Sagot :

MrRoyal

Answer:

[tex]a_n = 4.5 * 3^{n-1}[/tex]

Step-by-step explanation:

Given

[tex]a_4 = 121.5[/tex]

[tex]r = 3[/tex]

Required

[tex]a_n = a_1 * r^{n -1}[/tex]

Substitute 4 for n in [tex]a_n = a_1 * r^{n -1}[/tex]

[tex]a_4 = a_1 * r^{4 -1}[/tex]

[tex]a_4 = a_1 * r^3[/tex]

Substitute 121.5 for [tex]a_4[/tex]

[tex]121.5 = a_1 * 3^3[/tex]

[tex]121.5 = a_1 * 27[/tex]

Solve for a1

[tex]a_1 = \frac{121.5}{27}[/tex]

[tex]a_1 = 4.5[/tex]

So, we have:

[tex]a_n = a_1 * r^{n -1}[/tex]

[tex]a_n = 4.5 * 3^{n-1}[/tex]

freazefire0

Answer:

First I substituted 121.5 for an, 4 for n, and 3 for r in the general form. Then I solved to find a1 = 4.5. Finally, I substituted 4.5 for a1 and 3 for r in the general form to get an = 4.5 ⋅ 3n−1.

Step-by-step explanation:

sample answer on edge ;)

Thank you for visiting our platform. We hope you found the answers you were looking for. Come back anytime you need more information. Thank you for visiting. Our goal is to provide the most accurate answers for all your informational needs. Come back soon. Thank you for trusting Westonci.ca. Don't forget to revisit us for more accurate and insightful answers.