Question

Dibantu ya beserta penyelesaiannya​

Answer 1

a = (1, 3, 2)

⃗b = (p, 0, 4)

⃗a x ⃗b = 1xp + 3x0 + 2x4

⃗a x ⃗b = p + 8

|b| = √( p² + 0₂ + 4²)

|b| = √(p² + 16)

proyeksi vektor ⃗a pada ⃗b (c)

c = ⃗a x ⃗b/|b|

c = (p + 8)/√(p² + 16)

11/5 = (p + 8)/√(p² + 16)

11√(p² + 16) = 5(p + 8)

[11√(p² + 16)]² = (5p + 40)²

121(p² + 16) = 25p² + 400p + 1600

121p² + 1936 = 25p² + 400p + 1600

121p² - 25² - 400p + 1936 - 1600

96p² - 400p + 336 = 0

6p² - 25 + 21 = 0

(6p - 7)(p - 3) = 0

p = 7/6 dan

p = 3........(C)