A logic circuit consist of two 2 × 4 decoder as shown below

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A logic circuit consist of two 2 × 4 decoder as shown below is—

The output of decoder are as follow
D₀ = 1 when A₀ = 0, A₁ = 0
D₁ = 1 when A₀ = 1, A₁ = 0
D₂ = 1 when A₀ = 0, A₁ = 1
D₃ = 1 when A₀ = 1, A₁ = 1
The value of f (x, y, z) is—

1. 0
2. z
3. –z
4. 1

Correct Option: D

From figure

D₂ = xy
D₃ = xy
A₁ = D₂D₃ = xy.xy = 0
and f = A₁ A₀ + A₁ A₀
= A₁ (A₀ + A₀ )
= A₁ = 0 = 1
(∵ A₁ = D₂D₃ = 0)
Hence alternative (D) is the correct choice.