If r = l(b x c) + m(c x a ) + n(a x b) and [a b c ] - Maths - Vector Algebra

Question

If r = l(b x c) + m(c x a ) + n(a x b) and [a b c ] = 2, then l
+ m + n is equal to
a r [(b x c) + (c x a) + (a x b)]
b 1/2 r (a + b + c)
c [a b c ]
d none of these
Note that : r, a, b, and c are the vector
quantities

Suresh Kumar · Answer

Please find the answer
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If r = l(b x c) + m(c x a ) + n(a x b) and [a b c ] = 2, then l + m + n is equal to a. r.[(b x c) + (c x a) + (a x b)] b. 1/2 r.(a + b + c) c. [a b c ] d. none of these Note that : r, a, b, and c are the vector quantities.

If r = l(b x c) + m(c x a ) + n(a x b) and [a b c ] = 2, then l + m + n is equal to

a. r.[(b x c) + (c x a) + (a x b)]

b. 1/2 r.(a + b + c)

c. [a b c ]

d. none of these

Note that : r, a, b, and c are the vector quantities.