Q. If a1=9 and an+1=2an+2 then find the value of a5.Answer:
Identify Given Sequence: Identify the given sequence and the recursive formula.We are given the first term of the sequence, a1=9, and the recursive formula an+1=2an+2, which tells us how to find any term in the sequence based on the previous term.
Find a2: Use the recursive formula to find a2. We know a1=9, so we can find a2 by plugging a1 into the recursive formula: a2=2a1+2a2=2×9+2a2=18+2a2=20
Find a3: Use the recursive formula to find a3. Now that we have a2, we can find a3: a3=2a2+2a3=2×20+2a3=40+2a3=42
Find a4: Use the recursive formula to find a4. With a3 found, we can find a4: a4=2a3+2a4=2×42+2a4=84+2a4=86
Find a5: Use the recursive formula to find a5. Finally, we use a4 to find a5: a5=2a4+2a5=2×86+2a5=172+2a5=174
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