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Question
Let f: N → R be the function defined by f(x) = `(2x - 1)/2` and g: Q → R be another function defined by g(x) = x + 2. Then (g o f) `3/2` is ______.
Options
1
1
`7/2`
None of these
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Solution
Let f: N → R be the function defined by f(x) = `(2x - 1)/2` and g: Q → R be another function defined by g(x) = x + 2. Then (g o f) `3/2` is none of these.
Explanation:
We have f(x) = `(2x - 1)/2` and g(x) = x + 2
gof`(3/2)` = g`(f(3/2))`
= `"g"((2 xx 3/2 - 1)/2)`
= g(1) = 1 + 2
= 3
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