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What is the area of the parallelogram whose sides are represented by the vectors i + 2 j + 3 k and 2 i + j + 2 k ?

Options

  1. A1 2 26 square units
  2. B1 2 27 square units
  3. C26 square units
  4. D27 square units

Correct answer

C. 26 square units

Step-by-step solution

Let a = i + 2 j + 3 k and b = 2 i + j + 2 k . The area of the parallelogram with adjacent sides a and b is given by | a b | . a b = vmatrix i & j & k 1 & 2 & 3 2 & 1 & 2 vmatrix = i (4 - 3) - j (2 - 6) + k (1 - 4) = i + 4 j - 3 k The magnitude of the cross product is: | a b | = 1^2 + 4^2 + (-3)^2 = 1 + 16 + 9 = 26 The area of the parallelogram is 26 square units. Answer: 26 square units

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