- #1
Lebombo
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Homework Statement
Youtube: Lec 2 | MIT 18.02 Multivariable Calculus, Fall 2007 (Video time frame: between 11:00 minutes and 12:30 minutes)
Find the area of a triangle.
Area = [itex]\frac{1}{2}(base)(height)[/itex] = [itex]\frac{1}{2}|a||b|sinθ[/itex]
The lecturer says to first find cosine of the angle using dot product. Next, solve for sine using [sin[itex]^{2}θ + cos^{2}θ[/itex] = 1]. And then substitute into area formula.
However, he doesn't actually work this out, so I don't know what formula its supposed to produce or how to actually arrive there. This is a section on cross products so this might be a preface to the cross product formula and I'm interest to know where he was actually going with this. Any info would be very appreciated. Thanks.