Q. ⎩⎨⎧f(1)=37f(n)=f(n−1)⋅0.3Find an explicit formula for f(n).
Given initial condition: We are given the initial condition f(1)=37 and the recursive formula f(n)=f(n−1)×0.3. To find an explicit formula, we need to express f(n) in terms of n without the recursion.
Identify pattern in terms: Let's look at the first few terms to identify a pattern:f(1)=37f(2)=f(1)×0.3=37×0.3f(3)=f(2)×0.3=(37×0.3)×0.3=37×0.32We can see that with each step, we multiply by an additional factor of 0.3.
Generalize formula based on pattern: Based on the pattern, we can generalize that f(n)=37×0.3(n−1), where n is the term number.
Verify formula for n=1: To verify this formula, we can check it for n=1:f(1)=37×0.3(1−1)=37×0.30=37×1=37, which matches the given initial condition.
Verify formula for n=2: Now, let's check it for another value, say n=2:f(2)=37×0.3(2−1)=37×0.31=37×0.3=11.1, which matches the recursive definition f(2)=f(1)×0.3.