Page 202 - FUNDAMENTALS OF COMPUTER
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202                         Fundamentals of Computers                           NPP


                                                    0 = 00, 1 = 01, 3 = 11
                                                   A       B         F
                                                   0        0        1
                                                   0        1        1
                                                   1        0        0
                                                   1        1        1
                      (c) The given expression is:                (c) {X`m J`m ì`§OH$:
                                                    Q =    C . B . A  +  B . A  +  C . B . A
                       This expression is not in a canonical SOP  Ho$Zmo{ZH$b ê$n _| Zht h¡ Ÿ³¶m|{H$  .A B   ‘| Ho$db Xmo
                  form because  .A  B  has only two variables. C is
                  missing. Therefore to convert it into canonical  d¡[aE~b h¡& C Zht h¡& AV…  .A  B  H$mo (C +  C ) go JwUm
                  SOP form multiply by (C +  C ) to get:      H$aZo  na…
                                                     A.B =  .A  B  (C +  C )

                      or,             NPP                 C . B . A  +  C . B . A
                      Put it in the original equation:            Cnamoº$ _mZ ì`§OH$ _| aIZo na…
                                 Q =    C . B . A  +  C . B . A  +  C . B . A  +  C . B . A    =  + A.B.C  + A.B.C  A.B.C
                      Since  .A  C . B   is repeated, we can write once.  My±{H$ .A  C . B  Xmo ~ma Am J`m h¡, AV… h_ Cgo EH$
                  The three minterms give three 1s in the output.
                  The truth table can be drawn as:            hr ~ma {bI gH$Vo h¢ Ÿ& VrZ {_ÝQ>_© Ho$ gmnoj AmCQ>nwQ>
                                                              _| VrZ "1" hm|Jo…
                                              A         B         C       Q
                                              0         0          0       0
                                              0         0          1       1
                                              0         1          0       0
                                              0         1          1       0
                                              1         0          0       1
                                              1         0          1       1
                                              1         1          0       0
                                              1         1          1       0
                  Maxterms                                    _oŠgQ>_©
                      “Maxterms are fundamental sums corre-       _oŠgQ>_© "0" Ho$ gmnoj \§$S>m_|Q>b `moJ hmoVo h¢Ÿ& AWm©V²
                  sponding to ‘0’ in the output.” Consider the fol-  Ohm± AmCQ>nwQ> _| "0" àmßV hmo, Cg g§`moOZ Ho$ gmnoj
                  lowing truth table:                         \§$S>m_|Q>b `moJ àmßV {H$`m OmVm h¡, Cgo _oŠgQ>_© H$hVo
                                                              h¢Ÿ& {ZåZ gË`-Vm{bH$m H$mo g_Pmo…
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