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                  NPP               Number System, Boolean Algebra and Logic Circuits              231


                      (a)  F =  B . A  +  A  B .                  (b)  F =   C . B . A  +  C . B . A  +  C . B . A  +  C . B . A

                      (c)  F =  (A+ B+ C ) (A.  + B + C ) (A.  + B+ C )  (d)  Y =  Σ m ( 5,4  ) 7 ,

                      (e)  Y =  Σ m ( 1,0  , 9 , 8 , 7 , 3 ,  13 , 14 , 12 )  (f)   F = π M  (1, 3,6,7 )
                                                )
                      (g)  F = π M (2, 4, 7, 9, 12, 13, 15 .
                  Solution:                                   hc:

                      (a) The    given    expression     is       (a) Cnamoº$ g_rH$aU   F =  B . A  +  A  B .  hoVw K-
                  F =   B . A  +  A  B . . The Karnaugh map and group  _on VWm eyÝ` Ho$ J«wn Bg àH$ma ~Z|Jo:
                  of 0’s are as follows:
                                                       A  B  0     1


                                                        0    1     0


                                                        1    1     0

                      There is only one pair. When we move form   Cnamoº$ K- _on _| EH$ hr no`a h¡ Ÿ& D$na go ZrMo
                  top to bottom, A changes, therefore eliminate  OmZo na A n[ad{V©V hmoVm h¡ AV… Bgo hQ>m XmoŸ& My±{H$ B =
                  A. B is constant at ‘1’. Therefore write   B  .  1 na pñWa h¡, Bg{bE   B   {bImoŸ& `hr hb h¡:

                                                            F =  B
                      (b) The given expression is:                (b) {X`m J`m ì`§OH$:

                                               F =    C . B . A  +  C . B . A  +  C . B . A  +  C . B . A
                      The K-map and group of 0’s can be drawn     _| Mma {_ÝQ>_© h¢ AV… Mma 1 VWm Mma 0 H$s
                  as:
                                                              ghm`Vm go K- _on ~ZoJm d {ZåZmZwgma EH$ ŠdmS> ~ZoJm:
                                                 A  B C  00  01    11    10


                                                 0    1      1     0      0


                                                 1    1      1     0      0



                      There is only one quad for 0’s. For this quad  My±{H$ ŠdmS> _| D$na go ZrMo OmZo na A d ~mE§ go XmE§
                  A and C change. Therefore these variables are  OmZo na C  n[ad{V©V hmo ahm h¡, AV… A  d C XmoZm| H$mo
                  eliminated. B is constant at ‘1’. Therefore write
                  B  This is the solution.  F =  B            hQ>m Xmo & B=1 na pñWa h¡ AV…  B {bImo & `hr gab
                                                              ì`§OH$ h¡…  F =  B
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