Sponsor Area

Determinants

Question
CBSEENMA12034351

 The value of the determinant remains unchanged if its rows and columns are interchanged.Verify space the space property space for space space increment space equals space open vertical bar table row 2 cell space space minus 3 end cell cell space space 5 end cell row 6 cell space space space 0 end cell cell space space 4 end cell row 1 cell space space space 5 end cell cell space 7 end cell end table close vertical bar

Solution
space increment space equals space open vertical bar table row 2 cell space space minus 3 end cell cell space space 5 end cell row 6 cell space space space 0 end cell cell space space 4 end cell row 1 cell space space space 5 end cell cell space 7 end cell end table close vertical bar
Expanding space the space determinant space along space first space row comma space we space have
increment space space equals 2 space open vertical bar table row 0 cell space space space space space space 4 end cell row 5 cell space space minus 7 end cell end table close vertical bar minus left parenthesis negative 3 right parenthesis space open vertical bar table row 6 cell space space space space 4 end cell row 1 cell space space space minus 7 end cell end table close vertical bar space plus 5 space open vertical bar table row 6 cell space space 0 end cell row 1 cell space space 5 end cell end table close vertical bar
space space space space space equals space 2 left parenthesis 0 minus 20 right parenthesis plus 3 left parenthesis negative 42 minus 4 right parenthesis plus 5 left parenthesis 30 minus 0 right parenthesis equals negative 40 minus 138 plus 150 equals negative 28
By space interchanging space rows space and space columns comma space we space get
increment subscript 1 space equals space space space space open vertical bar table row 2 cell space space minus 3 end cell cell space space 5 end cell row 6 cell space space space 0 end cell cell space space 4 end cell row 1 cell space space space 5 end cell cell space 7 end cell end table close vertical bar space equals 2 space space open vertical bar table row 0 cell space space space space space space 4 end cell row 5 cell space space minus 7 end cell end table close vertical bar minus left parenthesis negative 3 right parenthesis space open vertical bar table row 6 cell space space space space 4 end cell row 1 cell space space space minus 7 end cell end table close vertical bar space plus 5 space open vertical bar table row 6 cell space space 0 end cell row 1 cell space space 5 end cell end table close vertical bar
space space space space space equals 2 space left parenthesis 0 minus 20 right parenthesis plus 3 left parenthesis negative 42 minus 4 right parenthesis plus 5 left parenthesis 30 minus 0 right parenthesis
space space space space space equals negative 40 minus 138 plus 150 equals negative 28
therefore space space space increment space equals space increment subscript 1 space
Hence space property space is space verified.

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