Question

Find the first four terms of the sequence An=2a n-1,where a1=3

Answer 1

The first four terms of the sequence are 3 , 6 , 12 , 24

Step-by-step explanation:

We need to find the first four terms of the sequence $a_{n}=2a_{n-1}$

where $a_{1}=3$ to find them do that

• Substitute n by 2 in the rule to find $a_{2}$
• Substitute n by 3 in the rule to find $a_{3}$
• Substitute n by 4 in the rule to find $a_{4}$

∵ $a_{n}=2a_{n-1}$

- Substitute n by 2 to find the 2nd term

∴ $a_{2}=2a_{2-1}$

∴ $a_{2}=2a_{1}$

∵ $a_{1}=3$

∴ $a_{2}=2(3)$

∴ $a_{2}=6$

- Substitute n by 3 to find the 3rd term

∴ $a_{3}=2a_{3-1}$

∴ $a_{3}=2a_{2}$

∵ $a_{2}=6$

∴ $a_{3}=2(6)$

∴ $a_{3}=12$

- Substitute n by 4 to find the 4th term

∴ $a_{4}=2a_{4-1}$

∴ $a_{4}=2a_{3}$

∵ $a_{3}=12$

∴ $a_{4}=2(12)$

∴ $a_{4}=24$

The first four terms of the sequence are 3 , 6 , 12 , 24

Learn more:

You can learn more about the sequences in brainly.com/question/1522572

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