Question

Select the correct option from the given alternatives:

If `|bar"a"| = 2, |bar"b"| = 3, |bar"c"| = 4` then `[bar"a" + bar"b"    bar"b" + bar"c"    bar"c" - bar"a"]` is equal to

Options

• 24

• - 24

• 0

• 48

Answer 1

`[bar"a" + bar"b"    bar"b" + bar"c"    bar"c" - bar"a"]` = 0 

Explanation:

`(bara +barb).[(barb+barc)xx(barc-bara)]`

`=barbxxbarc-barbxxbara+barcxxbarc-barcxxbara`

`=(bara+barb).[barbxxbarc-barbxxbara-barcxxbara]`

`=bara.(barbxxbarc)-bara.(barbxxbara)-bara.(barcxxbara)+barb.(barbxxbarc)-barb.(barbxxbara)-barb.(barcxxbara)`

`=bara.(barbxxbarc)+0+0+0+0 - barb.(barcxxbara)`

`=(bara  barb  barc)-(bara  barb  barc)=0`