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Question
Find `vec"a"*vec"b"` when `vec"a" = 2hat"i" + 2hat"j" - hat"k"` and `vec"b" = 6hat"i" - 3hat"j" + 2hat"k"`
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Solution
`vec"a" = 2hat"i" + 2hat"j" - hat"k"` and `vec"b" = 6hat"i" - 3hat"j" + 2hat"k"`
`vec"a"*vec"b" = (2hat"i" + 2hat"j" - hat"k")*(6hat"i" - 3hat"j" + 2hat"k")`
= (2)(6) + (2)(– 3) + (–1)(2)
= 12 – 6 – 2
= 12 – 8
= 4
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