AP EAMCET · Maths · Trigonometric Ratios & Identities
\(\cos 12^{\circ}+\cos 60^{\circ}+\cos 84^{\circ}+\cos 132^{\circ}+\cos 156^{\circ}=\)
- A \(\frac{-1}{4}\)
- B \(\frac{-1}{2}\)
- C 0
- D \(\frac{1}{4}\)
Answer & Solution
Correct Answer
(C) 0
Step-by-step Solution
Detailed explanation
\( = \cos 12^{\circ} + \frac{1}{2} + \cos 84^{\circ} - \cos 48^{\circ} - \cos 24^{\circ} \) \( = \frac{1}{2} + (\cos 12^{\circ} - \cos 24^{\circ}) + (\cos 84^{\circ} - \cos 48^{\circ}) \)…
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Maths
- In \(\triangle \mathrm{ABC}\), if \(\mathrm{a}^2 \sin ^2 \frac{\mathrm{C}}{2}+\mathrm{c} \sin ^2 \frac{\mathrm{A}}{2}=\frac{\mathrm{b}}{2}\), then \(\mathrm{a}+\mathrm{c}: \mathrm{b}=\)AP EAMCET 2023 Easy
- The number of ways of arranging all the letters of the word PERFECTION such that there must be exactly two consonants between any two vowels isAP EAMCET 2025 Medium
- \(\int \frac{x}{\sqrt{x+1}+\sqrt{x-1}} d x=A(x)(x+1)^{\frac{3}{2}}+B(x)(x-1)^{\frac{3}{2}}+C\) , then \(A(x)+B(x)=\)AP EAMCET 2019 Hard
- If \(z=\frac{y}{x}\left[\sin \frac{x}{y}+\cos \left(1+\frac{y}{x}\right)\right]\), then \(x \frac{\partial z}{\partial x}\) is equal toAP EAMCET 2002 Hard
- If the distance \(s\) described in time ' \(t\) ' by a particle moving on a straight line is given by \(s=t^5-40 t^3+30 t^2+80 t-250\), then its minimum acceleration isAP EAMCET 2018 Medium
- \[
\left(4 \cos ^2 9^{\circ}-3\right)\left(4 \cos ^2 27^{\circ}-3\right)=
\]AP EAMCET 2022 Medium
More PYQs from AP EAMCET
- The volume of \(0.1 \mathrm{M} \mathrm{HCl}\) required in \(\mathrm{mL}\) to neutralise \(20 \mathrm{~mL}\) of a solution containing \(0.106 \mathrm{~g}\) of \(\mathrm{Na}_2 \mathrm{CO}_3\) isAP EAMCET 2018 Medium
- Calculate the amount of \(\mathrm{NO}_2\) required for producing \(4 \mathrm{~g}\) moles of \(\mathrm{HNO}_3\) as per the chemical reaction, \(3 \mathrm{NO}_2+\mathrm{H}_2 \mathrm{O} \longrightarrow 2 \mathrm{HNO}_3+\mathrm{NO}\). Given, the gram molecular weights of di-nitrogen and di-oxygen gases are \(28 \mathrm{~g}\) and \(32 \mathrm{~g}\) respectively.AP EAMCET 2020 Easy
- If the quadratic equation formed by eliminating \(x\) from \(x^2+\alpha x+\beta=0\) and \(x y+l(x+y)+m=0\) has the same roots as that of the given quadratic equation, then the set of values of \(\beta\) isAP EAMCET 2018 Medium
- If the osmotic pressure of cane sugar solution is \(2.46 \mathrm{~atm}\) at \(27^{\circ} \mathrm{C}\), then what is the concentration (in \(\mathrm{mol} \mathrm{L}^{-1}\) ) of the solution ( \(\left.\mathrm{R}=0.0821 \mathrm{~L} \mathrm{~atm} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}\right)\)AP EAMCET 2023 Medium
- If a normal chord at a point \(t\) on the parabola \(y^2=4 a x\) subtends a right angle at the vertex, then \(t\) equals toAP EAMCET 2014 Hard
- A point on the curve \(x=3 \cos \theta, y=2 \sin \theta\) at which the tangent is perpendicular to \(X\)-axis isAP EAMCET 2020 Easy