an identity involving trigonometric functions
Trigonometric Identity
sin(s+t) = ?
sin(s)cos(t) + cos(s)sin(t)
Allow us to find the values of the trigonometric functions at 2x from their values at x
Double-Angle Formula
Relate products of sines and cosines to sums of sines and cosines
Product-Sum Formula
sin2(x)+cos2(x) = ?
1
sin(θ)/cos(θ) + cos(θ)/(1+ sin(θ))
sec(θ)
cos(s-t) = ?
cos(s)cos(t) + sin(s)sin(t)
Relate the values of the trigonometric functions at 1/2x to their values at x
Half-Angle Formula
sin(u)cos(v) = ?
1/2[sin(u+v) + sin(u-v)]
Find the solution of one period.
cos(θ) = .65
θ is about .86, 5.42
Prove.
cos(θ)/1- sin(θ)= sec(θ) + tan(θ)
correct
tan(s+t) = ?
tan(s)+tan(t)/1-tan(s)tan(t)
tan(2) = ?
2tan(x)/1-tan2(x)
sin(u)sin(v) = ?
1/2[cos(u-v) - cos(u+v)]
sin(θ)=1/2
θ = π/6 + 2kπ and 5π/6 + 2kπ
Prove.
1+cos(θ)/cos(θ) = tan2(θ)/sec(θ)-1
sec(θ) + 1=sec(θ) + 1
Solve.
sin 20° cos 40° + sin 40° cos 20°
sin 60°= √3/2
Solve.
Sin(3x)/sin(x)cos(x)
4cos(x)- sec(x)
Write sin(7x) + sin(3x) as a product
2sin(5x)cos(2x)
2cos2θ - 7cosθ + 3 = 0
θ = π/3 + 2kπ and 5π/3 + 2kπ
Prove.
sec(x) + csc(x)/ tan(x) + cot(x)= cos(x)
No.
sin(x)=cos(x)
Evaluate sin(x+t), where sin(x)=12/13 with x in Quadrant II and tan(t)=3/4 with t in Quadrant III
-33/65
Find the exact value of sin 22.5°
(1/2)√ (2-√ 2)
Solve.
sin(3x)-sin(x) / cos(3x)+cos(x)
tan(x)
1 + sin(θ) = 2cos2(θ)
θ = π/6 + 2kπ and 5π/6 + 2kπ and 3π/3 + 2kπ