Q. If a1=1 and an=2an−1−5 then find the value of a5.Answer:
Given terms and formula: We are given the first term of the sequence, a1=1, and the recursive formula an=2an−1−5. To find a5, we need to find the values of a2, a3, a4, and then a5 using the recursive formula.
Find a2: Let's find a2 using the recursive formula:a2=2a1−5a2=2(1)−5a2=2−5a2=−3We have found that a2 is −3.
Find a3: Now let's find a3 using the recursive formula:a3=2a2−5a3=2(−3)−5a3=−6−5a3=−11We have found that a3 is −11.
Find a4: Next, we find a4 using the recursive formula:a4=2a3−5a4=2(−11)−5a4=−22−5a4=−27We have found that a4 is −27.
Find a5: Finally, we find a5 using the recursive formula:a5=2a4−5a5=2(−27)−5a5=−54−5a5=−59We have found that a5 is −59.
More problems from Find the roots of factored polynomials