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Consider the following statements : I...

Consider the following statements :
`I. lim_(n to oo) ( 2^n +(-2)^n)/(2^n) ` dos not exist
`II. lim_(n to oo) ( 3^n +(-3)^n)/(2^n) ` does not exist then

A

I is true and II is fals

B

I is false and II is true

C

I and II are true

D

neither I nor II is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given problem, we need to analyze the two statements regarding the limits as \( n \) approaches infinity. ### Step 1: Analyze the First Statement We need to evaluate the limit: \[ \lim_{n \to \infty} \frac{2^n + (-2)^n}{2^n} \] **Solution:** 1. Rewrite the expression: \[ \lim_{n \to \infty} \frac{2^n + (-2)^n}{2^n} = \lim_{n \to \infty} \left(1 + \frac{(-2)^n}{2^n}\right) \] 2. Simplify \(\frac{(-2)^n}{2^n}\): \[ \frac{(-2)^n}{2^n} = (-1)^n \] 3. Therefore, the limit becomes: \[ \lim_{n \to \infty} \left(1 + (-1)^n\right) \] 4. As \( n \) approaches infinity, \( (-1)^n \) oscillates between -1 and 1. Hence, the limit does not exist. **Conclusion for Statement I:** The first statement is **true**. ### Step 2: Analyze the Second Statement Now we evaluate the limit: \[ \lim_{n \to \infty} \frac{3^n + (-3)^n}{2^n} \] **Solution:** 1. Rewrite the expression: \[ \lim_{n \to \infty} \frac{3^n + (-3)^n}{2^n} = \lim_{n \to \infty} \left(\frac{3^n}{2^n} + \frac{(-3)^n}{2^n}\right) \] 2. Simplify each term: \[ \frac{3^n}{2^n} = \left(\frac{3}{2}\right)^n \quad \text{and} \quad \frac{(-3)^n}{2^n} = (-1)^n \left(\frac{3}{2}\right)^n \] 3. Therefore, the limit becomes: \[ \lim_{n \to \infty} \left(\left(\frac{3}{2}\right)^n + (-1)^n \left(\frac{3}{2}\right)^n\right) = \lim_{n \to \infty} \left(1 + (-1)^n\right) \left(\frac{3}{2}\right)^n \] 4. Since \(\left(\frac{3}{2}\right)^n\) approaches infinity as \( n \) approaches infinity, the limit diverges. **Conclusion for Statement II:** The second statement is **false** because the limit exists and approaches infinity. ### Final Conclusion - Statement I is true. - Statement II is false. ### Answer The correct option is: **First statement is true and second is false.**
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