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If f, g: R to R be defined by f(x)=2x+1 ...

If `f, g: R to R` be defined by `f(x)=2x+1` and `g(x) =x^(2)-2, AA x in R,` respectively. Then , find `gof` .

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To find \( g \circ f \) (read as "g of f"), we need to substitute the function \( f(x) \) into the function \( g(x) \). Let's go through the steps systematically. ### Step-by-Step Solution: 1. **Identify the Functions**: - We have \( f(x) = 2x + 1 \) - We have \( g(x) = x^2 - 2 \) 2. **Find \( g(f(x)) \)**: - We need to find \( g(f(x)) \), which means we will substitute \( f(x) \) into \( g(x) \). - Therefore, \( g(f(x)) = g(2x + 1) \). 3. **Substitute \( f(x) \) into \( g(x) \)**: - Now, substitute \( 2x + 1 \) into \( g(x) \): \[ g(2x + 1) = (2x + 1)^2 - 2 \] 4. **Expand \( (2x + 1)^2 \)**: - Use the identity \( (a + b)^2 = a^2 + 2ab + b^2 \): \[ (2x + 1)^2 = (2x)^2 + 2 \cdot (2x) \cdot 1 + 1^2 = 4x^2 + 4x + 1 \] 5. **Subtract 2**: - Now, we will subtract 2 from the expanded expression: \[ g(2x + 1) = 4x^2 + 4x + 1 - 2 \] \[ g(2x + 1) = 4x^2 + 4x - 1 \] 6. **Final Result**: - Therefore, \( g \circ f = g(f(x)) = 4x^2 + 4x - 1 \). ### Summary: The composition of the functions \( g \) and \( f \) is given by: \[ g \circ f = 4x^2 + 4x - 1 \]

To find \( g \circ f \) (read as "g of f"), we need to substitute the function \( f(x) \) into the function \( g(x) \). Let's go through the steps systematically. ### Step-by-Step Solution: 1. **Identify the Functions**: - We have \( f(x) = 2x + 1 \) - We have \( g(x) = x^2 - 2 \) ...
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