LIVE Course for free

Rated by 1 million+ students
Get app now
JEE MAIN 2023
JEE MAIN 2023 TEST SERIES
NEET 2023 TEST SERIES
NEET 2023
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
19 views
in Mathematics by (90.2k points)
closed by
Select and write the appropriate answer from the given alternatives in each of the following sub- questions:
if `hata = 3hati - hatj + 4hatk, barb = 2hati + 3hatj - hatk, barc = - 5 hat i + 2hatj + 3hatk` then `bara . (barb xx barc)` = ……….
A. 100
B. 101
C. 110
D. 109

1 Answer

0 votes
by (91.7k points)
selected by
 
Best answer
We have `bara = 3hati- hatj + 4hatk `
` barb = 2hatj + 3hatk + hatk`
`barc = - 5hati + 2hatj + 3 hatk`
`barb xx barc = |{:(hati , hatj ,hatk),(2,3,-1),(-5,2,3):}|`
`hati (9+ 2) - hatj (6-5)hatk + (4+ 5)`
`= 11 hati - hatj + 19hatk`
`bara.(barb xx barc) = (3hati- hatj + 4hatk).(11hati- hatjk + 19 hatk)`
` = 33 + 1 + 76`
= 110
Hence, the correct answer from the given alternatives is (c).

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...