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If f(x)=x^(2) and g(x)=2x , then evaluat...

If `f(x)=x^(2) and g(x)=2x` , then evaluate,
(i) `(f+g)(3)" "(ii) (f-g)(2)`
(iii) `(f*g)(1)" "(iv) ((f)/(g))(5)`

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To solve the problem, we need to evaluate the following expressions using the given functions \( f(x) = x^2 \) and \( g(x) = 2x \): 1. \( (f + g)(3) \) 2. \( (f - g)(2) \) 3. \( (f \cdot g)(1) \) 4. \( \left( \frac{f}{g} \right)(5) \) Let's evaluate each one step by step. ### Step 1: Evaluate \( (f + g)(3) \) **Solution:** - First, we need to find \( f(3) \) and \( g(3) \). - \( f(3) = 3^2 = 9 \) - \( g(3) = 2 \cdot 3 = 6 \) - Now, we add these two results: \[ (f + g)(3) = f(3) + g(3) = 9 + 6 = 15 \] ### Step 2: Evaluate \( (f - g)(2) \) **Solution:** - Next, we find \( f(2) \) and \( g(2) \). - \( f(2) = 2^2 = 4 \) - \( g(2) = 2 \cdot 2 = 4 \) - Now, we subtract \( g(2) \) from \( f(2) \): \[ (f - g)(2) = f(2) - g(2) = 4 - 4 = 0 \] ### Step 3: Evaluate \( (f \cdot g)(1) \) **Solution:** - We need to find \( f(1) \) and \( g(1) \). - \( f(1) = 1^2 = 1 \) - \( g(1) = 2 \cdot 1 = 2 \) - Now, we multiply these two results: \[ (f \cdot g)(1) = f(1) \cdot g(1) = 1 \cdot 2 = 2 \] ### Step 4: Evaluate \( \left( \frac{f}{g} \right)(5) \) **Solution:** - We find \( f(5) \) and \( g(5) \). - \( f(5) = 5^2 = 25 \) - \( g(5) = 2 \cdot 5 = 10 \) - Now, we divide \( f(5) \) by \( g(5) \): \[ \left( \frac{f}{g} \right)(5) = \frac{f(5)}{g(5)} = \frac{25}{10} = 2.5 \] ### Final Answers: 1. \( (f + g)(3) = 15 \) 2. \( (f - g)(2) = 0 \) 3. \( (f \cdot g)(1) = 2 \) 4. \( \left( \frac{f}{g} \right)(5) = 2.5 \)
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