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Let [x] denot the greatest integer `le x`. If `f (x)= [x] and g(x)=|x|` then the value of `f(g((8)/(5)))-g(f(-(8)/(5)))` is

A

2

B

`-2`

C

1

D

`-1`

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The correct Answer is:
To solve the problem, we need to evaluate the expression \( f(g(\frac{8}{5})) - g(f(-\frac{8}{5})) \) where \( f(x) = [x] \) (the greatest integer less than or equal to \( x \)) and \( g(x) = |x| \) (the absolute value of \( x \)). ### Step-by-Step Solution: 1. **Calculate \( g(\frac{8}{5}) \)**: \[ g\left(\frac{8}{5}\right) = \left|\frac{8}{5}\right| = \frac{8}{5} \] Since \( \frac{8}{5} \) is positive, the absolute value remains the same. 2. **Calculate \( f(g(\frac{8}{5})) \)**: \[ f(g(\frac{8}{5})) = f\left(\frac{8}{5}\right) = f(1.6) \] To find \( f(1.6) \), we take the greatest integer less than or equal to \( 1.6 \): \[ f(1.6) = [1.6] = 1 \] 3. **Calculate \( f(-\frac{8}{5}) \)**: \[ f\left(-\frac{8}{5}\right) = f(-1.6) \] To find \( f(-1.6) \), we take the greatest integer less than or equal to \( -1.6 \): \[ f(-1.6) = [-1.6] = -2 \] 4. **Calculate \( g(f(-\frac{8}{5})) \)**: \[ g(f(-\frac{8}{5})) = g(-2) = |-2| = 2 \] 5. **Combine the results**: Now we substitute back into the original expression: \[ f(g(\frac{8}{5})) - g(f(-\frac{8}{5})) = 1 - 2 = -1 \] ### Final Answer: The value of \( f(g(\frac{8}{5})) - g(f(-\frac{8}{5})) \) is \( -1 \).
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