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If a function f:QtoR is defined by f(x)=...

If a function `f:QtoR` is defined by `f(x)=(2x-1)/(2)` and function `g:QtoR` is defined by `g(x)=(2x-1)/(2)`, then `(gof)((3)/(2))` is

A

1

B

2

C

`(7)/(2)`

D

none of these

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The correct Answer is:
To solve the problem, we need to find \( (g \circ f)\left(\frac{3}{2}\right) \), which means we first need to evaluate \( f\left(\frac{3}{2}\right) \) and then use that result to evaluate \( g \) at that value. ### Step 1: Evaluate \( f\left(\frac{3}{2}\right) \) The function \( f \) is defined as: \[ f(x) = \frac{2x - 1}{2} \] Now, substitute \( x = \frac{3}{2} \): \[ f\left(\frac{3}{2}\right) = \frac{2\left(\frac{3}{2}\right) - 1}{2} \] ### Step 2: Simplify the expression Calculating the numerator: \[ 2 \cdot \frac{3}{2} = 3 \] So we have: \[ f\left(\frac{3}{2}\right) = \frac{3 - 1}{2} = \frac{2}{2} = 1 \] ### Step 3: Evaluate \( g(1) \) Next, we need to evaluate \( g(1) \) using the function \( g \), which is defined as: \[ g(x) = \frac{2x - 1}{2} \] Now substitute \( x = 1 \): \[ g(1) = \frac{2(1) - 1}{2} \] ### Step 4: Simplify the expression Calculating the numerator: \[ 2 \cdot 1 = 2 \] So we have: \[ g(1) = \frac{2 - 1}{2} = \frac{1}{2} \] ### Final Result Thus, the value of \( (g \circ f)\left(\frac{3}{2}\right) \) is: \[ \frac{1}{2} \]
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ICSE-RELATIONS AND FUNCTIONS -MULTIPLE CHOICE QUESTIONS
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  8. If a function f:RtoR is defined by f(x)=(x^(2)-5)/(x^(2)+4), then f is

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  15. which of the following functions from ZtoZ is a bijection ?

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  17. If f:RtoR is defined by f(x)=ax+b,ane0 then f^(-1)(x)

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