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The vertices of ΔABC are A (3, 5, −4), B (−1, 1, 2),...

The vertices of ΔABC are A (3, 5, | Class 12 Mathematics Chapter Three Dimensional Geometry, Three Dimensional Geometry NCERT Solutions

Question:

The vertices of ΔABC are A (3, 5, −4), B (−1, 1, 2), and C (−5, −5, −2).

Answer:

The vertices of ΔABC are A (3, 5, −4), B (−1, 1, 2), and C (−5, −5, −2).

vertices of triangle ABC

The direction ratios of side AB are (−1 − 3), (1 − 5), and (2 − (−4)) i.e., −4, −4, and 6.

direction cosines of AB

Therefore, the direction cosines of AB are

direction of cosines of AB

The direction ratios of BC are (−5 − (−1)), (−5 − 1), and (−2 − 2) i.e., −4, −6, and −4.

Therefore, the direction cosines of BC are

direction cosines of BC

The direction ratios of CA are (−5 − 3), (−5 − 5), and (−2 − (−4)) i.e., −8, −10, and 2.

Therefore, the direction cosines of AC are

direction cosines of AC

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Welcome to the NCERT Solutions for Class 12 Mathematics - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 5: The vertices of ΔABC are A (3, 5, −4), B (−1, 1, 2), and C (−5, −5, &m....

The vertices of ΔABC are A (3, 5, | Class 12 Mathematics Chapter Three Dimensional Geometry, Three Dimensional Geometry NCERT Solutions

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