Simplify the Trig Expression:
tan(θ)cos(θ)
sin(θ)
(1 + cosx)/(sinx) = cscx + cotx
(1 + cosx)/(sinx) =
(1/sinx) + (cosx/sinx) =
cscx + cotx
Solve the Equation on the interval [0,2π)
2cos2θ = sinθ + 1
π, π/6, 3π/2
What type of Identity is this:
cscθ = 1/sinθ
Reciprocal Identity
Sine, cosine, and tangent are all positive in this quadrant.
Quadrant 1
sin(θ)csc(θ) - sin2(θ)
cos2(θ)
Verify the Trig Identity:
cosx(tan2x + 1) = sec(x)
cosx(tan2x + 1)
cosx(sec2x)
cosx(1/cos2x)
1/cosx
sec(x)
Solve the equation over the interval [0,2π)
4sin2(3θ) - 3 = 0
π/9, 2π/9, 4π/9, 5π/9
What type of Identity is this:
sin2θ + cos2θ = 1
Pythagorean Identity
Simplify sin(π/6)
1/2
Simplify the Trig Expression:
(secθ/cscθ) + (sinθ/cosθ)
2tanθ
(1 - tan2x)/(1 + tan2x) = 1-2sin2x
(1 - tan2x)/(1 + tan2x) =
(1 - tan2x)/(sec2x) =
(1 / sec2x) - (tan2x/sec2x) =
cos2x - sin2x =
(1 - sin2x) - sin2x =
1 - 2sin2x
Solve the equation and give the general solution:
4cosx = 1 + 2cosx
π/3 = 2πn, 5π/3 + 2πn
where n is an integer
What type of Identity is this:
tanθ = sinθ/cosθ
Ratio Identity
Simplify tan(2π/3)
√3
(sin4x - cos4x) / (sin2x - cos2x)
1
Verify the Trig Identity:
(sinx + cosx)2 + (sinx - cosx)2 = 2
(sinx + cosx)2 + (sinx - cosx)2
sin2x + 2cosxsinx + cos2x + sin2x - 2cosxsinx + cos2x
2sin2x + 2cos2x
2(sin2x + cos2x)
2(1)
2
Solve the equation over the interval [0,2π)
3tan4x- 10tan2x = -3
π/6, 5π/6, 7π/6, 11π/6, π/3, 2π/3, 4π/3, 5π/3
What type of Identity are these:
cos(-θ) = cosθ & sin(-θ) = -sinθ
Even/Odd Formulas
The cosine of an angle is equal to √2/2 at these two angles.
Pi/4 and 7Pi/4 (45 and 315 degrees).
Simplify the Trig Expression:
sec(-x) + tan(-x)cos(𝝅/2 - x)
cos(x)
Verify the Trig Identity:
(1/(sinx - 1)) - (1/(sinx + 1)) = -2sec2x
(1/(sinx - 1)) - (1/(sinx + 1)) =
(sinx + 1 - sinx + 1)/(sin2x -1) =
2/(-cos2x) =
-2sec2x
Solve the equation and give the general solution:
2sin(3x) - √2 = 0
π/12 + (2πn)/3, π/4 + (2πn)/3
Where n is an integer
What type of Identity are these:
cos(π/2 - θ) = sinθ
Cofunction Identity
On the unit circle, you can find tangent this way.
What is divide y by x?