Question

The sides of a triangle are in the ratio $$1:\sqrt 3 :2,$$   then the angles of the triangle are in the ratio

A. 1 : 3 : 5
B. 2 : 3 : 4
C. 3 : 2 : 1
D. 1 : 2 : 3  
Answer :   1 : 2 : 3
Solution :
Sides are in the Ration $$1:\sqrt 3 :2$$
$$\eqalign{ & {\text{Let }}a = k,b = \sqrt 3 k\,\,{\text{and }}c = 2k \cr & \cos A = \frac{{{b^2} + {c^2} - {a^2}}}{{2bc}} = \frac{{\sqrt 3 }}{2} \cr & \Rightarrow \,\,A = \frac{\pi }{6} \cr & \cos B = \frac{{{c^2} + {a^2} - {b^2}}}{{2ac}} = \frac{1}{2} \cr & \Rightarrow \,\,B = \frac{\pi }{3} \cr & \Rightarrow \,\,C = \pi - \left( {A + B} \right) = \frac{\pi }{2} \cr & \Rightarrow \,\,A:B:C = 1:2:3 \cr} $$

Releted MCQ Question on
Trigonometry >> Properties and Solutons of Triangle

Releted Question 1

If the bisector of the angle $$P$$ of a triangle $$PQR$$  meets $$QR$$  in $$S,$$ then

A. $$QS = SR$$
B. $$QS : SR = PR : PQ$$
C. $$QS : SR = PQ : PR$$
D. None of these
Releted Question 2

From the top of a light-house 60 metres high with its base at the sea-level, the angle of depression of a boat is 15°. The distance of the boat from the foot of the light house is

A. $$\left( {\frac{{\sqrt 3 - 1}}{{\sqrt 3 + 1}}} \right)60\,{\text{metres}}$$
B. $$\left( {\frac{{\sqrt 3 + 1}}{{\sqrt 3 - 1}}} \right)60\,{\text{metres}}$$
C. $${\left( {\frac{{\sqrt 3 + 1}}{{\sqrt 3 - 1}}} \right)^2}{\text{metres}}$$
D. none of these
Releted Question 3

In a triangle $$ABC,$$  angle $$A$$ is greater than angle $$B.$$ If the measures of angles $$A$$ and $$B$$ satisfy the equation $$3\sin x - 4{\sin ^3}x - k = 0, 0 < k < 1,$$       then the measure of angle $$C$$ is

A. $$\frac{\pi }{3}$$
B. $$\frac{\pi }{2}$$
C. $$\frac{2\pi }{3}$$
D. $$\frac{5\pi }{6}$$
Releted Question 4

In a triangle $$ABC,$$  $$\angle B = \frac{\pi }{3}{\text{ and }}\angle C = \frac{\pi }{4}.$$     Let $$D$$ divide $$BC$$  internally in the ratio 1 : 3 then $$\frac{{\sin \angle BAD}}{{\sin \angle CAD}}$$   is equal to

A. $$\frac{1}{{\sqrt 6 }}$$
B. $${\frac{1}{3}}$$
C. $$\frac{1}{{\sqrt 3 }}$$
D. $$\sqrt {\frac{2}{3}} $$

Practice More Releted MCQ Question on
Properties and Solutons of Triangle


Practice More MCQ Question on Maths Section