Answered

Discover new knowledge and insights with IDNLearn.com's extensive Q&A database. Our platform is designed to provide reliable and thorough answers to all your questions, no matter the topic.

Find a + b, 9a + 3b, |a|, and |a − b|. a = 9i − 4j + 3k, b = 6i − 9k

Sagot :

ItzTdsidn

1) a + b = ?

→ (9i − 4j + 3k) + (6i − 9k)

→ 15i - 4j - 6k

2) 9a + 3b = ?

→ 9(9i − 4j + 3k) + 3(6i − 9k)

→ (81i - 36j + 27k) + (18i - 27k)

→ 99i - 36j

3) |a| = ?

→ |9i − 4j + 3k|

→ 9i + 4j + 3k

4) |a − b| = ?

→ |(9i − 4j + 3k) - (6i − 9k)|

→ |3i - 4j + 12k|

→ 3i + 4j + 12k

Semsee45idn

Answer:

[tex]a+b=15i-4j-6k[/tex]

[tex]9a+3b=99i-36j[/tex]

[tex]|a| = 9i+4j+3k[/tex]

[tex]|a-b| = 3i+4j+12k[/tex]

Step-by-step explanation:

Given:

[tex]\begin{cases}a = 9i-4j+3k\\b=6i-9k\end{cases}[/tex]

[tex]\begin{aligned}a+b & = (9i-4j+3k)+(6i-9k)\\& = 9i-4j+3k+6i-9k\\& = 9i+6i-4j+3k-9k\\& = 15i-4j-6k\\\end{aligned}[/tex]

[tex]\begin{aligned}9a+3b & = 9(9i-4j+3k) + 3(6i-9k)\\& = 81i-36j+27k+ 18i-27k\\& = 81i+ 18i-36j+27k-27k\\& = 99i-36j\end{aligned}[/tex]

[tex]\begin{aligned}|a| & = |9i-4j+3k|\\& = 9i+4j+3k\end{aligned}[/tex]

[tex]\begin{aligned}|a-b| & = |(9i-4j+3k)-(6i-9k)|\\& = |9i-4j+3k-6i+9k|\\& = |9i-6i-4j+3k+9k|\\& = |3i-4j+12k|\\& = 3i+4j+12k\end{aligned}[/tex]

We appreciate your contributions to this forum. Don't forget to check back for the latest answers. Keep asking, answering, and sharing useful information. For trustworthy answers, rely on IDNLearn.com. Thanks for visiting, and we look forward to assisting you again.