AP EAMCET · Maths · Trigonometric Ratios & Identities
If then
- A
- B
- C
- D
Answer & Solution
Correct Answer
(A)
Step-by-step Solution
Detailed explanation
cos2A+cos2B+cos2C =2cosA+BcosA-B+cos2C ∵cosC+cosD=2cosC+D2cosC-D2 =2cos3π2-CcosA-B+1-2sin2C ∵A+B+C=3π2 & cos2θ=1-2sin2θ =1-2sinCcosA-B-2sin2C =1-2sinCcosA-B+sin3π2-A+B ∵A+B+C=3π2 =1-2sinCcosA-B-cosA+B =1-4sinAsinBsinC…
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
- Given, \(\sin x=\sum_{n=1}^{\infty}(-1)^{n-1} \frac{x^{2 n-1}}{(2 n-1) !}\). If the function \(f(x)\) given by \(f(x)=\frac{\cos (\sin x)-\cos x}{x^4}(x \neq 0)\) and \(f(0)=k\), is continuous at \(x=0\), then \(k=\)AP EAMCET 2019 Hard
- \(\int e^{3 \log x}\left(x^4+1\right)^{-1} d x=\)AP EAMCET 2020 Medium
- Let \(\omega=\operatorname{cis}\left(\frac{2 \pi}{3}\right)=\cos \left(\frac{2 \pi}{3}\right)+i \sin \left(\frac{2 \pi}{3}\right)\) and \(f(x)=x^7-2 x^4-4 x^3+8\). Which of the following option is correct?AP EAMCET 2021 Medium
- \(\operatorname{Tanh}^{-1}(\sin \theta)=\)AP EAMCET 2025 Medium
- If \(\left[\begin{array}{ccc}5 & a & -7 \\ b & -7 & c \\ -7 & d & -1\end{array}\right]\) is the adjoint of the matrix \(\left[\begin{array}{lll}1 & 2 & 3 \\ 2 & 3 & 1 \\ 3 & 1 & 2\end{array}\right]\), then \(a+b+c+d=\)AP EAMCET 2022 Easy
- What is the greatest angle of the triangle whose sides are \(x^2+x+1,2 x+1, x^2-1\) ?AP EAMCET 2021 Hard
More PYQs from AP EAMCET
- If the ratio of specific heats of a gas at constant pressure and at constant volume is \(\gamma\), then the number of degrees of freedom of the rigid molecules of the gas isAP EAMCET 2025 Medium
- If \(y=f(x)\) is a thrice differentiable function and a bijection then that \(\frac{d^2 x}{d y^2}\left(\frac{d y}{d x}\right)^3+\frac{d^2 y}{d x^2}=\)AP EAMCET 2024 Easy
- A \(100 \mathrm{~L}\) cylinder containing \(\mathrm{H}_2\) exerted a pressure of \(4 \mathrm{~atm}\) at \(300 \mathrm{~K}\). It was accidentally opened and some \(\mathrm{H}_2\) was escaped. When it was closed, it exerted a pressure of \(3 \mathrm{~atm}\) at \(300 \mathrm{~K}\). The number of moles of \(\mathrm{H}_2\) remaining in the cylinder is equal to
(Assume \(\mathrm{H}_2\) as an ideal gas; \(\mathrm{R}=\) gas constant)AP EAMCET 2023 Medium - \(\int \frac{x^2-1}{x^3 \sqrt{2 x^4-2 x^2+1}} d x\)AP EAMCET 2024 Medium
- A real value of will satisfy the equation , ifAP EAMCET 2021 Medium
- Which of the following represents the correct order of ionic radii?AP EAMCET 2018 Easy