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1. Three vectors are given by A = 3i+ 3j - 2k, B = i-4j+ 2k and C= 4i-j + 2k Show that A x (B+C) = (A x B) + (AXC)​

User Amjad Khan
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Answer:

Step-by-step explanation:

First, let's find A x (B+C):

A x (B+C) = A x B + A x C (distributive property of cross product over vector addition)

Now, we need to find A x B and A x C separately:

A x B = (3i + 3j - 2k) x (i - 4j + 2k) (using the cross product formula)

= (31 + 32) i - (34 - 21) j + (3*(-2) - 3*1) k

= 9i + 10j - 9k

Similarly,

A x C = (3i + 3j - 2k) x (4i - j + 2k)

= (34 - 2(-1)) i - (32 + 31) j + (31 - 34) k

= 14i - 9j - 9k

Now, we can substitute these values into the original equation:

A x (B+C) = A x B + A x C

(3i + 3j - 2k) x [(i - 4j + 2k) + (4i - j + 2k)] = (9i + 10j - 9k) + (14i - 9j - 9k)

Simplifying the right side:

(9i + 10j - 9k) + (14i - 9j - 9k) = 23i + 1j - 18k

Now, let's calculate the left side:

(3i + 3j - 2k) x [(i - 4j + 2k) + (4i - j + 2k)]

= (3i + 3j - 2k) x (5i - 5j + 4k)

= (35 + 24) i - (3*(-5) + 34) j + (35 - 2*(-5)) k

= 23i + 1j + 15k

Therefore, we have:

23i + 1j - 18k = 23i + 1j + 15k

Since the left and right sides are equal, we have shown that:

A x (B+C) = A x B + A x C.

User Stataq
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