Q. f(n)=45⋅(54)n−1Complete the recursive formula of f(n).f(1)=□f(n)=f(n−1)⋅□
Given Explicit Formula: We are given the explicit formula for the sequence:f(n)=45×(54)n−1To find the recursive formula, we need to express f(n) in terms of f(n−1).
Find f(1): First, let's find f(1) by substituting n=1 into the explicit formula:f(1)=45×(54)1−1=45×(54)0=45×1=45This gives us the initial condition for the recursive formula.
Express f(n) in terms of f(n−1): Now, let's find f(n) in terms of f(n−1). We know that:f(n)=45×(54)n−1f(n−1)=45×(54)(n−1)−1=45×(54)n−2
Divide f(n) by f(n−1): To express f(n) in terms of f(n−1), we divide f(n) by f(n−1): f(n−1)f(n)=45×(54)n−245×(54)n−1 Simplifying the right side, we get: f(n−1)f(n)=(54)
Multiplying to get Recursive Formula: Multiplying both sides by f(n−1), we get the recursive formula:f(n)=f(n−1)×(54)
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