JAWABAN 1731130033 BAGAS ADI PRAYOGO
JAWABAN SOAL1
A x B = - B x A
10i + 9j + 16k = - (3i + 2j -3k)(2i - 4j + k)
= - 6 + 12k + 3j + 4k + 8 - 2i + 6j + 12i + 3
= 16 k + 9j + 10i
10i + 9j + 16k = 10i + 9j + 16k
A+B = (2i - 4j + k ) + (3i + 2j - 3k )
= 6 + 4k + 6j + 12k - 8 + 12i + 3j - 2i - 3
= 16k + 9j + 10i
= 10i + 9j + 16k
JAWABAN SOAL2
R = 2i + 6j - k
|R| = (√2 + √ 6 - √ 1 )
= √ 4 + √36 - √1
= √ 40 - √1
= √ 39
S = 4j - 6k
|s| = √ 4 - √ 6
= √ 16 - √36
= √ 20
Cos x = S . R / |S| |R|
= (8 - 12 + 1 - 24 - 36 + 4 - 6) / √39 + √20
= - 65 / √59
Cos x = - 8. 4°
A x B = - B x A
10i + 9j + 16k = - (3i + 2j -3k)(2i - 4j + k)
= - 6 + 12k + 3j + 4k + 8 - 2i + 6j + 12i + 3
= 16 k + 9j + 10i
10i + 9j + 16k = 10i + 9j + 16k
A+B = (2i - 4j + k ) + (3i + 2j - 3k )
= 6 + 4k + 6j + 12k - 8 + 12i + 3j - 2i - 3
= 16k + 9j + 10i
= 10i + 9j + 16k
JAWABAN SOAL2
R = 2i + 6j - k
|R| = (√2 + √ 6 - √ 1 )
= √ 4 + √36 - √1
= √ 40 - √1
= √ 39
S = 4j - 6k
|s| = √ 4 - √ 6
= √ 16 - √36
= √ 20
Cos x = S . R / |S| |R|
= (8 - 12 + 1 - 24 - 36 + 4 - 6) / √39 + √20
= - 65 / √59
Cos x = - 8. 4°