# Question and Answers Forum

TrigonometryQuestion and Answers: Page 1

determinant ()
cos (((2π)/(21)))cos (((4π)/(21)))cos (((8π)/(21)))cos (((10π)/(22)))cos (((16π)/(21)))cos (((20π)/(21)))=?
(1/(cos x−cos 3x)) + (1/(cos x−cos 5x)) + (1/(cos x−cos 7x)) + (1/(cos x−cos 11x))=?
3(sinθ − cosθ)^4 + 6(sinθ + cosθ)^2 + 4(sin^6 θ + cos^6 θ) = ?
Relating to question 207407 x^3 −12x^2 +27x−17=0 Let x=t+4 t^3 −21t−37=0 The Trigonometric Solution gives these: x_1 =4−2(√7)cos ((π+2sin^(−1) ((37(√7))/(98)))/6) x_2 =4−2(√7)sin ((sin^(−1) ((37(√7))/(98)))/3) x_3 =4+2(√7)sin ((π+sin^(−1) ((37(√7))/(98)))/3) Prove these identities: x_1 =2−((1+2sin (π/(18)))/(2cos (π/9))) x_2 =2+((1+2cos (π/9))/(2cos ((2π)/9))) x_3 =((1+2(√3)sin ((2π)/9))/(2sin (π/(18))))
f(x)=[cos2x+cos3x][cos4x+cos6x][[cosx+cos5x] evaluar f(((2π)/(13)))
Construct an angle whose sine is (3/(2 + (√5))) .
If sinθ = ((m^2 + 2mn)/(m^2 + 2mn + 2n^2 )) then prove that tanθ = ((m^2 + 2mn)/(2mn + 2n^2 )) .
If tanθ = ((2x(x + 1))/(2x + 1)) then find sinθ and cosθ.
If A = sin^4 θ + cos^4 θ then select the correct option: i) 0 < A < (1/2) ii) 1 < A < (3/2) iii) (1/2) ≤ A ≤ 1 iv) (3/2) ≤ A ≤ 2
If asin^2 θ + bcos^2 θ = c, bsin^2 φ + acos^2 φ = d and atanθ = btanφ then prove that (1/a) + (1/b) = (1/c) + (1/d) .
If asinθ = bcosθ = ((2ctanθ)/(1 − tan^2 θ)) then prove that (a^2 − b^2 )^2 = 4c^2 (a^2 + b^2 ).
If tan^2 θ = 1 − x^2 then prove that secθ + tan^3 θcosecθ = (√((2 − x^2 )^3 )) .
If tanpθ = ptanθ then prove that ((sin^2 pθ)/(sin^2 θ)) = (p^2 /(1 + (p^2 − 1)sin^2 θ)) .
sin(π/7) × sin((2π)/7) × sin((3π)/7) = ?
Prove that 2^(sin^2 θ) + 2^(cos^2 θ) ≥ 2(√2).
If, ϕ = (1/2) (π −cos^( −1) ((1/4) )) ⇒ log_( 2) ( (( 1+ cos(6ϕ ))/(cos^6 (ϕ ))) ) =?

Terms of Service

Privacy Policy

Contact: info@tinkutara.com