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Two functions f:R to R and g:Rto R are d...

Two functions `f:R to R and g:Rto R` are defined as follows:
`f(x)={{:(,0,x in Q),(,1,x ne Q):},g(x)={{:(,-1,x in Q),(,0,x in Q):}`
Then, fof (e)+fog`(pi)`

A

`-1`

B

0

C

1

D

2

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to evaluate the expression \( g(f(e)) + f(g(\pi)) \) using the definitions of the functions \( f \) and \( g \). ### Step-by-Step Solution: 1. **Identify the nature of \( e \) and \( \pi \)**: - Both \( e \) and \( \pi \) are irrational numbers. 2. **Evaluate \( f(e) \)**: - The function \( f(x) \) is defined as: \[ f(x) = \begin{cases} 0 & \text{if } x \in \mathbb{Q} \\ 1 & \text{if } x \notin \mathbb{Q} \end{cases} \] - Since \( e \) is irrational, we have: \[ f(e) = 1 \] 3. **Evaluate \( g(f(e)) \)**: - Now we need to find \( g(f(e)) = g(1) \). - The function \( g(x) \) is defined as: \[ g(x) = \begin{cases} -1 & \text{if } x \in \mathbb{Q} \\ 0 & \text{if } x \notin \mathbb{Q} \end{cases} \] - Since \( 1 \) is a rational number, we have: \[ g(1) = -1 \] 4. **Evaluate \( g(\pi) \)**: - We now need to find \( g(\pi) \). - Since \( \pi \) is also irrational, we have: \[ g(\pi) = 0 \] 5. **Evaluate \( f(g(\pi)) \)**: - Now we need to find \( f(g(\pi)) = f(0) \). - Since \( 0 \) is a rational number, we have: \[ f(0) = 0 \] 6. **Combine the results**: - Now we can combine the results to find the final expression: \[ g(f(e)) + f(g(\pi)) = -1 + 0 = -1 \] ### Final Answer: The value of \( g(f(e)) + f(g(\pi)) \) is \( -1 \).

To solve the problem, we need to evaluate the expression \( g(f(e)) + f(g(\pi)) \) using the definitions of the functions \( f \) and \( g \). ### Step-by-Step Solution: 1. **Identify the nature of \( e \) and \( \pi \)**: - Both \( e \) and \( \pi \) are irrational numbers. 2. **Evaluate \( f(e) \)**: ...
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