Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) §11.3 Cross Products and Determinants, #43 · Multivariable Calculus · Vectors & geometry

By Problem 42 find the area … of the triangle with corners…

These problems compute the areas of triangles.

By Problem 42 find the area $A$ of the triangle with corners $(2, 1)$ and $(4, 2)$ and $(1, 2)$ . Where is a fourth corner to make a parallelogram?

This exercise builds on another exercise in its source book, which isn't shown here.

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Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) · §11.3 Cross Products and Determinants, #43

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