Saved Bookmarks
| 1. |
Given A = i - 2j +3k and B = 3i - 2j + k find 2A + 5B. |
|
Answer» We have A = \(\hat i\) - 2\(\hat j\) + 3\(\hat k\) and 3 = 3\(\hat i\) - 2\(\hat j\) + \(\hat k\) 2A + 5B = 2(\(\hat i\) - 2\(\hat j\) + 3\(\hat k\)) + 5 (3\(\hat i\) - 2\(\hat j\) + \(\hat k\)) = (2\(\hat i\) - 4\(\hat j\) + 6\(\hat k\) ) + (15\(\hat i\) - 10\(\hat j\) + 5\(\hat k\)) = (2 + 15)\(\hat i\) - (4 + 10)\(\hat j\) + (6 + 5)\(\hat k\) = 17 \(\hat i\) - 14 \(\hat j\) + 11\(\hat k\) |
|