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Question
Find `vec"a"*vec"b"` when `vec"a" = hat"i" - 2hat"j" + hat"k"` and `vec"b" = 3hat"i" - 4hat"j" - 2hat"k"`
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Solution
`vec"a" = hat"i" - 2hat"j" + hat"k"` and `vec"b" = 3hat"i" - 4hat"j" - 2hat"k"`
`vec"a" * vec"b" = (hat"i" - 2hat"j" + hat"k")*(3hat"i" - 4hat"j" - 2hat"k")`
= (1)(3) + (– 2)(– 4) + (1)(– 2)
= 3 + 8 – 2
= 9
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