JEE Mains · Maths · STD 11 - Trigonometrical equations
If the angles of elevation of the top of a tower from threecollinear points \(A, B\) and \(C\) on a line leading to the foot of the tower are \(30^o , 45^o \) and \(60^o \) respectively, then the ratio \(AB : BC\) is:
- A \(2 :3\)
- B \(\sqrt 3 :1\)
- C \(\;\sqrt 3 :\sqrt 2 \)
- D \(\;1:\sqrt 3 \)
Answer & Solution
Correct Answer
(B) \(\sqrt 3 :1\)
Step-by-step Solution
Detailed explanation
\(AB=\sqrt 3 x-x\) \(BC=x-\frac{x}{\sqrt 3}\) \(\frac{AB}{BC}=\frac{\sqrt 3 x-x}{x-\frac{x}{\sqrt 3}}\)\(=\frac{\sqrt 3}{1}\)
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