a) Determine the cosine of the angles of the triangle whose vertices are A(1, –2,1), B(3,0, 2), C(0, 1, –3).b) Determine whether the angle at the vertex A is obtuse or acute. Justify your answer.

a) Determine the cosine of the angle of the triangle whose vertices are A(1,-2,1), B(3,0,2),…

Answered: a) Determine the cosine of the angles…

Holt Mcdougal Larson Pre-algebra: Student Edition 2012

1st Edition

ISBN:9780547587776

Author:HOLT MCDOUGAL

Publisher:HOLT MCDOUGAL

Chapter12: Angle Relationships And Transformations

Section12.3: Angles And Polygons

Problem 18E

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a) Determine the cosine of the angles of the triangle whose vertices are A(1, –2,1), B(3,0, 2), C(0, 1, –3). b) Determine whether the angle at the vertex A is obtuse or acute. Justify your answer.