Jawaban:

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Penjelasan dengan langkah-langkah:

V E K T O R

15. E

a × b = 0

(1, 2, –3) × (4, 4, m) = 0

4 + 8 – 3m = 0

–3m = –12

m = 4

18. E

A(5, 4, 1)

B(9, 2, –3)

AB = (4, –2, –4)

|AB| = √(4)²+(–2)²+(–4)²

|AB| = √(16+4+16)

|AB| = √(36)

|AB| = 6

19.

a(3, –4)

b(7, 1)

c(-2, -5)

2a – b + 4c

= (6–7–8, –8–1–20)

= (–9, –29)

23. B

jarak P ke Q adalah 4 satuan ke kanan dan 3 satuan ke atas

PQ = (4, 3)

|PQ| = √(4²+3²) = √25

|PQ| = 5

24. C

â(5, 2)

b(–2, 3)

a.b = –10+6

a.b = –4

25. E

u(–2, 5)

v(a, 4)

u.v = 8

–2a + 20 = 8

a = 6

v.v = 6²+4²

v.v = 36+16

v.v = 52

26.

a(–1, 2, 3)

b(1, –2, –2)

2a + 3b = (–2, 4, 6) + (3, –6, –6)

|2a + 3b| = √(–2+3)²+(4–6)²+(6–6)²

|2a + 3b| = √(1+4+0)

|2a + 3b| = √5