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Vectors and matrices — Question 15

QCAA 2020, Paper 2 · 4 marks

Q15 · 2020 · Technology-activeSimple familiar4 marks

QUESTION 15 (4 marks)

The position vectors of points P and Q are 2i^−3j^+k^2\hat{\mathbf i}-3\hat{\mathbf j}+\hat{\mathbf k} and 2i^+2j^−4k^2\hat{\mathbf i}+2\hat{\mathbf j}-4\hat{\mathbf k} respectively. Let O be the origin.
a)
Determine the angle POQ.
[2 marks]
b)
Points O, P and Q are joined to form a triangle. Determine the area of triangle POQ.
[2 marks]
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