proyeksi vektor ortogonal a = 2i + xj + k pada b = 3i + 2j + k adalah c = 1/14(-3i + 2j - k). nilai x =

Ralat soal, harusnya b = (3, -2, 1)

c = ( a.b / |b|² ) b
1/14 (-3, 2, -1) = [(6 + 2x + 1) / (9 + 1 + 4)] (3, -2, 1)
1/14 (-3, 2, -1) = (7+2x)/14 (3, -2, 1)
(-3, 2, -1) = (7+2x) (3, -2, 1)
-3 = (7+2x) . 3
7+2x = -1
2x = -8
x = -4