In a Δ ABC, the value of (b + c) cos A + (c + a) cos B + (a + b) cos – McqOptions

MCQOPTIONS

1.	In a Δ ABC, the value of (b + c) cos A + (c + a) cos B + (a + b) cos C is equal to
A.	0
B.	rR
C.	Rr2
D.	a + b + c
Answer» E.

Discussion

No Comment Found

Related MCQs

If A = 30°, B = 60° and C = 135°, then what is the value of sin3A + cos3B + tan3C – 3sin A cos B tan C?
If sec2 θ - sec θ = 1, then what is the value of tan12 θ - 3 tan10 θ + 3 tan8 θ - tan6 θ ?
If \(\tan α = \frac {m}{m + 1};\;(m \ne -1)\) and \(\tan β = \frac {1}{2m + 1};\) then α + β is equal to:
If Cosec θ = 25/7, then what is the value of Cot θ?
If x = cosecA + cosA and y = cosec A - cosA, then find the value of \((\frac{2}{x+y})^2 + (\frac{x-y}{2})^2 - 1\)
If cos θ + sin θ = m and sec θ + cosec θ = n, then what is the value of \(\frac{{\rm{n}}}{2}\left( {{{\rm{m}}^2} - 1} \right)?\)
cos2 90° + cosec2 90° - cot2 45° = ?
For 0° < θ < 90°, tanθ + cotθ = 2. θ is equal to:
Find the value of cos(A + B), if tan A = 3/4 and tan B = 5/12 and A and B are in quadrant I.
In ∆PQR, measure of angle Q is 90°. If cosecP = 17/15, and PQ = 0.8 cm, then what is the length (in cm) of side QR?