MCQ
In the Boolean algebra $(\overline {\bar A \cdot \bar B} ) \cdot A$ equals to
- A$\overline {A + B} $
- ✓$A$
- C$\overline {A \cdot B} $
- D$A + B$
✓
Answer
Correct option: B.
$A$
b
(b) $(\overline {\bar A \cdot \bar B} ) \cdot A = (\overline{\overline A} + \overline{\overline B} ) \cdot A = (A + B) \cdot A$
$= A \cdot A + AB = A + AB = A(1 + B) = A$
(b) $(\overline {\bar A \cdot \bar B} ) \cdot A = (\overline{\overline A} + \overline{\overline B} ) \cdot A = (A + B) \cdot A$
$= A \cdot A + AB = A + AB = A(1 + B) = A$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A cord is wound round the circumference of wheel of radius $r$. The axis of the wheel is horizontal and moment of inertia about it is $I$. A weight $mg$ is attached to the end of the cord and falls from rest. After falling through a distance $h$, the angular velocity of the wheel will be
→Two beams of light having intensities $I$ and $4\,I$ interfere to produce a fringe pattern on a screen. The phase difference between the two beams are $\pi / 2$ and $\pi / 3$ at points $A$ and $B$ respectively. The difference between the resultant intensities at the two points is $x I$. The value of $x$ will be.
→The four identical capacitors in the circuit shown below are initially uncharged. The switch is then thrown first to position $A$, and then to position $B$. After this is done:
→Note: $V_{1,2,3,4}$ are the potential differences across $C_{1,2,3,4}$ and $Q_{1,2,3,4}$ are the final charges stored in $C_{1,2,3,4}$ respectively.
In the Young’s double slit experiment with sodium light. The slits are $0.589 m$ a part. The angular separation of the third maximum from the central maximum will be (given $\lambda$ $= 589 mm$)
→The radius of hydrogen atom in its ground state is $5.3 \times {10^{ - 11}}m$. After collision with an electron it is found to have a radius of $21.2 \times {10^{ - 11}}m$. What is the principal quantum number $n$ of the final state of the atom $n=.........$
→An electron with energy $0.1\,ke\,V$ moves at right angle to the earth's magnetic field of $1 \times 10^{-4}\,Wbm ^{-2}$. The frequency of revolution of the electron will be. (Take mass of electron $=9.0 \times 10^{-31}\,kg$ )
→Air of density $1.2\,kg\,m^{-3}$ is blowing across the horizontal Wings of an aeroplane in such a way that its speeds above and below the wings are $150\,ms^{-1}$ and $100\,ms^{-1}$, respectively. The pressure difference between the upper and lower sides of the Wings, is ........ $Nm^{-2}$
→Which of the following plots may represent the reactance of a series $LC$ combination
→A wire of length $L$ is bent in the form of a circular coil and current $i$ is passed through it. If this coil is placed in a magnetic field then the torque acting on the coil will be maximum when the number of turns is
→A body of mass $m$ starts moving from rest along $x-$ axis so that its velocity varies as $v = a\sqrt s$ where $a$ is a constant and $s$ is the distance covered by the body. The total work done by all the forces acting on the body in the first second after the start of the motion is
→