In a triangle $ABC,{\rm{if}}\;\angle A = 60^\circ ,a = 5,b = 4$, then $c$ is a root of the equation

JEE MATHEMATICS MCQ: PROPERTIES OF TRIANGLES

1 Easy

1 of 1

Application +4 | -1

In a triangle

ABC,\mathrm{if}\;\angle A = 60^\circ ,a = 5,b = 4

, then

c

is a root of the equation

View answer and explanation

Correct option: B

{c^2} - 4c - 9 = 0

Option B (

{c^2} - 4c - 9 = 0

) is correct because it is the quadratic equation derived from applying the cosine rule with the given triangle properties.

Practice All Chapter MCQs →

{p_1},{p_2},{p_3}

\Delta \;ABC

A,B,C

\Delta

p_1^{ - 2} + p_2^{ - 2} + p_3^{ - 2}

5k,\;6k,\;5k

k

\Delta \,ABC

a = \left( {b - c} \right)\sec \theta

\frac{{2\,\sqrt {bc} }}{{b - c}}\,\,\sin \,\,\frac{A}{2} =

\Delta \;ABC,\frac{{b + c}}{a}

\Delta = {a^2} - {\left( {b - c} \right)^2}

\Delta

\Delta \;ABC

\tan A

A

2 s