Download App

Trigonometry – II — Maths STD 11 Science — Question

Maharashtra BoardEnglish MediumSTD 11 ScienceMathsTrigonometry – II2 Marks
MCQ
$\cos A +\cos \left(240^{\circ}+ A \right)+\cos \left(240^{\circ}- A \right)=$
  • A
    cos A
  • ✓
    $0$
  • C
    $\sqrt{3} \sin A$
  • D
    $\sqrt{3} \cos A$
✓

Answer

Correct option: B.
$0$
(B)
$\cos A +\cos \left(240^{\circ}+ A \right)+\cos \left(240^{\circ}- A \right)$
$=\cos A +2 \cos 240^{\circ} \cos A$
$=\cos A \left\{1+2 \cos \left(180^{\circ}+60^{\circ}\right)\right\}$
$=\cos A \left\{1+2\left(-\frac{1}{2}\right)\right\}$
= 0

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "MCQ" from Trigonometry – II→Trigonometry – II — all question types→Maths STD 11 Science question papers→Maharashtra Board STD 11 Science question papers→Maharashtra Board question paper generator→

Similar questions

Mapping f : R $\rightarrow$ R which is defined as f(x) = cos x, x $\in$ R will be
→
If $\tan\alpha=\frac{\text{x}}{\text{x}+1}\text{ and }\tan\beta=\frac{1}{2\text{x}+1},$ than $\alpha+\beta$ is equal to
→
If $A$ lies in second quadrant $3\tan\text{A}+4=0,$ then the value of $2\cot\text{A}-5\cot\text{A}+\sin\text{A}$ is :
→
If $\text{z}=\frac{1}{(2+3\text{i})^2},$ then $|\text{z}|=$
→
The equation of the ellipse whose one focus is at $(4,0)$ and whose eccentricity is $\frac{4}{5}$, is
→
Which one of the following is not a function?
→
If $f(x)\left\{\begin{array}{rr}\log \left(\sec ^2 x\right)^{\cot 2 x}, & \text { for } x \neq 0 \\ K+1, & \text { for } x=0\end{array}\right.$ is continuous at $x=0$, then value of $K$ is
→
Consider two events A and B such that $P ( A )=\frac{1}{4}, P \left(\frac{ B }{ A }\right)=\frac{1}{2}, P \left(\frac{ A }{ B }\right)=\frac{1}{4}$. For each of the following statements, which is true
I. $P \left( A ^{ c } / B ^{ c }\right)=\frac{3}{4}$
II. The events A and B are mutually exclusive
III. $P ( A / B )+ P \left( A / B ^{ c }\right)=1$
→
If $z$ is a complex number, then which of the following is not true?
→
Which of the following functions is continuous at $x=0$ ?
→