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If p=7i+3j+2k and q=4i+5j-3k, find:

(i) the cosine angle between p and q,
(ii) the magnitude of p,
(iii) the magnitude of q,
(iv) the scalar product of p.q

User Aguayma
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1 Answer

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Final answer:

The cosine angle between p and q is 0.663. The magnitude of p is √(62) and the magnitude of q is √(50). The scalar product of p and q is 37.

Step-by-step explanation:

(i) To find the cosine angle between p and q, we need to calculate the dot product of p and q and divide it by the product of their magnitudes. The dot product of p and q is given by:

p · q = 7*4 + 3*5 + 2*(-3) = 28 + 15 - 6 = 37

The magnitude of p is given by:

|p| = √(7² + 3² + 2²) = √(62)

The magnitude of q is given by:

|q| = √(4² + 5² + (-3)²) = √(50)

Thus, the cosine angle between p and q is given by:

cosθ = (p · q) / (|p| * |q|) = 37 / (√(62) * √(50)) = 37 / √(3100) = 37 / 55.77 ≈ 0.663

(ii) The magnitude of p is |p| = √(7² + 3² + 2²) = √(62).

(iii) The magnitude of q is |q| = √(4² + 5² + (-3)²) = √(50).

(iv) The scalar product of p and q is given by:

p · q = 7*4 + 3*5 + 2*(-3) = 28 + 15 - 6 = 37.

User Lokesh Tiwari
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