# Solving Equations using Identities

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How to Solve Equations using Trig Identities?

Trigonometry : Solving Equations using identities (Example 1)
Worked solution to a trig. equation using the identity sin x / cos x = tan x
Example:
Solve sin θ - cos θ = 0 for 0° ≤ θ ≤ 360°.
Trigonometry : Solving Equations using identities (Example 2)
Worked solution to a trig. equation using the identity sin2 x + cos2 x = 1
Example:
Solve 3 - 3cos θ = 2sin2 θ for -180° ≤ θ ≤ 180°.

Trigonometry : Solving Equations using identities (Example 3)
Worked solution to a trig. equation using the identity sin2 x + cos2 x = 1
Example:
Solve 5sin θ + 3coc2 θ = 5 for 0° ≤ θ ≤ 360°.

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