Q. If a1=10 and an+1=−3an+5 then find the value of a4.Answer:
Given Information: We are given the first term of the sequence, a1=10, and the recursive formula an+1=−3an+5. To find a4, we need to find a2, a3, and then a4 using the recursive formula.
Find a2: First, let's find a2 using the recursive formula with n=1. a2=−3a1+5 a2=−3(10)+5 a2=−30+5 a2=−25
Find a3: Next, we'll find a3 using the recursive formula with n=2.a3=−3a2+5a3=−3(−25)+5a3=75+5a3=80
Find a4: Finally, we'll find a4 using the recursive formula with n=3.a4=−3a3+5a4=−3(80)+5a4=−240+5a4=−235
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