MHT CET202012 Oct 2020Morning ShiftMathematicsVector AlgebraActual

If [ a b c ]=4 , then volume of parallelopiped with coterminus edges a +2 b , b +2 c , c +2 a is

Options

A36 units ³
B32 units ³
C20 units ³
D40 units ³

Correct answer

A. 36 units ³

Step-by-step solution

Given a ( b c )=4 Volume of parallelopiped array l =( a +2 b ) [( b +2 c ) ( c +2 a )] =( a +2 b ) [( b c )+2( b a )+2( c c )+4( c a )] =[ a ( b c )]+[2 a ( b a )]+[4 a ( c a )]+ =[2 b ( b c )]+[4 b ( b a )]+[8 b ( c a )] =[ a ( b c )]+0+[8 b ( c a )] =9[ a ( b c )]=9(4)=36 array

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