Class 11MathematicsTrigonometrical EquationsMix Examples-Trigonometrical Equations and Inequations, Properties of Triangles, Height and Distance
MediumIn $\Delta ABC$,the expression $a(\cos^2 B + \cos^2 C) + \cos A(c \cos C + b \cos B)$ is equal to:
- A$a$
- B$b$
- C$c$
- D$a+b+c$
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DifficultAP EAMCET 2018
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