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Class 12 Three Dimensional Geometry · Assertion Reason1 Marksequations_of_lines

Class 12 Maths · Three Dimensional Geometry · Assertion Reason #27

Assertion (A): The line through (1,2,3),(5,−4,−7) is r=(1,2,3)+t(5,−4,−7). Reason (R): The line through position vectors a,b is r=a+t(b−a).

(A) Both A and R are true, and R correctly explains A.
(B) Both A and R are true, but R does not correctly explain A.
(C) A is true but R is false.
(D) A is false but R is true.

✅ Step-by-Step Solution

Final Answer: Option (D): A is false but R is true.

The required direction is (4,−6,−10), not (5,−4,−7).

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