If (a1, b1, c1) and (a2, b2, c2) be the direction ratios of two parall

1.	If (a1, b1, c1) and (a2, b2, c2) be the direction ratios of two parallel lines thenA. a1 = a2, b1 = b2, c1 = c2 B. \(\cfrac {a_1}{a_2}=\cfrac{b_1}{b_2}=\cfrac{c_1}{c_2}\)C. \(a_1^2+b_1^2+c_1^2=a_2^2+b_2^2+c_2^2\)D. a1a2 + b1b2 + c1c2 = 0
Answer» Correct option is B.\(\cfrac {a_1}{a_2}=\cfrac{b_1}{b_2}=\cfrac{c_1}{c_2}\) We know that if there is two parallel lines then their direction ratios must have a relation \(\cfrac {a_1}{a_2}=\cfrac{b_1}{b_2}=\cfrac{c_1}{c_2}\)

If (a1, b1, c1) and (a2, b2, c2) be the direction ratios of two parallel lines thenA. a1 = a2, b1 = b2, c1 = c2 B. \(\cfrac {a_1}{a_2}=\cfrac{b_1}{b_2}=\cfrac{c_1}{c_2}\)C. \(a_1^2+b_1^2+c_1^2=a_2^2+b_2^2+c_2^2\)D. a1a2 + b1b2 + c1c2 = 0

Answer»

Correct option is B.\(\cfrac {a_1}{a_2}=\cfrac{b_1}{b_2}=\cfrac{c_1}{c_2}\)

We know that if there is two parallel lines then their direction ratios must have a relation

\(\cfrac {a_1}{a_2}=\cfrac{b_1}{b_2}=\cfrac{c_1}{c_2}\)