NCERT Exercise 11.2 Q3 - Introduction to Three Dimensional Geometry
Question: Verify: (i) (0, 7, -10), (1, 6, -6), (4, 9, -6) form an isosceles triangle; (ii) (0, 7, 10), (-1, 6, 6), (-4, 9, 6) form a right-angled triangle; (iii) (-1, 2, 1), (1, -2, 5), (4, -7, 8), (2, -3, 4) are vertices of a parallelogram.
Answer: (i) yes, with two equal sides; (ii) yes, right-angled at the second point; (iii) yes, the diagonals have the same midpoint (3/2, -5/2, 9/2).
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