Math, asked by helpinghand6268, 1 year ago

The third term of a geometric sequence is 64 and the eighth term is -2,048. What is the first term?

Answers

Answered by suhaasneel22
2

Answer:

16

Step-by-step explanation:

Let the first term be a and the common ratio r

Use the formula for the n'th term: xn = arn - 1

The third term = 64 ⇒ x3 = ar3 - 1 = 64 ⇒ ar2 = 64 (1)

The eighth term = -2,048 ⇒ x8 = ar8 - 1 = -2,048 ⇒ ar7 = -2,048 (2)

Divide (2) by (1)⇒ r5 = -2,048/64 = -32 ⇒ r = -2

Substitute r = -2 into (1) ⇒ a × (-2)2 = 64 ⇒ a × 4 = 64 ⇒ a = 64 ÷ 4 =16  

The first term is 16

Answered by anilkumar9711078496
0

Answer:


Step-by-step explanation:


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