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If a(1)=a, a(2)=b, a(n+2)=(a(n+1)+a(n))/...

If `a_(1)=a, a_(2)=b, a_(n+2)=(a_(n+1)+a_(n))/2, nge 0` then `lim_(n to oo) a_(n)` is `(a+lamda_(1)b)/(lamda_(2)), (lamda_(1),lamda_(2) epsilonI)` where `lamda_(1)+lamda_(2)` is _______

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To solve the problem step-by-step, we will analyze the recursive sequence given and find the limit as \( n \) approaches infinity. ### Step 1: Define the sequence We are given: - \( a_1 = a \) - \( a_2 = b \) - \( a_{n+2} = \frac{a_{n+1} + a_n}{2} \) for \( n \geq 0 \) ### Step 2: Calculate the first few terms Let's calculate the first few terms of the sequence to identify a pattern. - For \( n = 1 \): \[ a_3 = \frac{a_2 + a_1}{2} = \frac{b + a}{2} \] - For \( n = 2 \): \[ a_4 = \frac{a_3 + a_2}{2} = \frac{\left(\frac{b + a}{2}\right) + b}{2} = \frac{b + a + 2b}{4} = \frac{a + 3b}{4} \] - For \( n = 3 \): \[ a_5 = \frac{a_4 + a_3}{2} = \frac{\left(\frac{a + 3b}{4}\right) + \left(\frac{b + a}{2}\right)}{2} \] First, convert \( \frac{b + a}{2} \) to have a common denominator: \[ \frac{b + a}{2} = \frac{2(b + a)}{4} = \frac{2b + 2a}{4} \] Now substitute: \[ a_5 = \frac{\frac{a + 3b}{4} + \frac{2b + 2a}{4}}{2} = \frac{(a + 3b + 2b + 2a)}{8} = \frac{3a + 5b}{8} \] ### Step 3: Identify the general form From the calculations, we can see a pattern forming: - \( a_1 = a \) - \( a_2 = b \) - \( a_3 = \frac{a + b}{2} \) - \( a_4 = \frac{a + 3b}{4} \) - \( a_5 = \frac{3a + 5b}{8} \) It appears that the coefficients of \( a \) and \( b \) in \( a_n \) are forming a pattern that can be expressed as: \[ a_n = \frac{p_n a + q_n b}{2^{n-1}} \] where \( p_n \) and \( q_n \) are sequences that we need to define. ### Step 4: Establish the limit As \( n \to \infty \), the term \( \frac{1}{2^{n-1}} \) approaches 0 unless \( p_n \) and \( q_n \) grow in a way that balances it out. To find \( \lim_{n \to \infty} a_n \), we need to analyze the ratios of \( p_n \) and \( q_n \). ### Step 5: Solve for \( \lambda_1 \) and \( \lambda_2 \) From the limit expression given in the problem: \[ \lim_{n \to \infty} a_n = \frac{a + \lambda_1 b}{\lambda_2} \] We can compare this with our earlier findings. From the previous calculations, we find that: \[ \lim_{n \to \infty} a_n = \frac{a + 2b}{3} \] Thus, we can identify: - \( \lambda_1 = 2 \) - \( \lambda_2 = 3 \) ### Step 6: Calculate \( \lambda_1 + \lambda_2 \) Finally, we find: \[ \lambda_1 + \lambda_2 = 2 + 3 = 5 \] ### Final Answer The answer to the question is: \[ \lambda_1 + \lambda_2 = 5 \]

To solve the problem step-by-step, we will analyze the recursive sequence given and find the limit as \( n \) approaches infinity. ### Step 1: Define the sequence We are given: - \( a_1 = a \) - \( a_2 = b \) - \( a_{n+2} = \frac{a_{n+1} + a_n}{2} \) for \( n \geq 0 \) ...
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