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Solving trigonometric equations using doubleangle identities
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Review these basic concepts…
Reference angle
Find the exact value of trigonometric ratios
ASTC rule in trigonometry (All Students Take Calculus)
Doubleangle identities
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Get Started NowChapter 18.17 Playlist
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Chapter 18 Topics:

18.1
Solving first degree trigonometric equations

18.2
Determining nonpermissible values for trig expressions

18.3
Solving second degree trigonometric equations

18.4
Solving expressions using 454590 special right triangles

18.5
Solving expressions using 306090 special right triangles

18.6
Find the exact value of trigonometric ratios

18.7
ASTC rule in trigonometry (All Students Take Calculus)

18.8
Sine graph: y = sin x

18.9
Cosine graph: y = cos x

18.10
Tangent graph: y = tan x

18.11
Cotangent graph: y = cot x

18.12
Secant graph: y = sec x

18.13
Cosecant graph: y = csc x

18.14
Solving trigonometric equations involving multiple angles

18.15
Solving trigonometric equations using pythagorean identities

18.16
Solving trigonometric equations using sum and difference identities

18.17
Solving trigonometric equations using doubleangle identities

18.18
Use sine ratio to calculate angles and side (Sin = $\frac{o}{h}$ )

18.19
Using cosine ratio to calculate angles and side (Cos = $\frac{a}{h}$ )

18.20
Use tangent ratio to calculate angles and side (Tan = $\frac{o}{a}$)

18.21
Combination of SohCahToa questions

18.22
Pythagorean theorem

18.23
Unit circle

18.24
Sine law

18.25
Cosine law

18.26
Word problems relating ladder in trigonometry

18.27
Word problems relating guy wire in trigonometry

18.28
Other word problems relating angles in trigonometry
Don't just watch, practice makes perfect.
Do better in math today
Chapter 18 Topics:

18.1
Solving first degree trigonometric equations

18.2
Determining nonpermissible values for trig expressions

18.3
Solving second degree trigonometric equations

18.4
Solving expressions using 454590 special right triangles

18.5
Solving expressions using 306090 special right triangles

18.6
Find the exact value of trigonometric ratios

18.7
ASTC rule in trigonometry (All Students Take Calculus)

18.8
Sine graph: y = sin x

18.9
Cosine graph: y = cos x

18.10
Tangent graph: y = tan x

18.11
Cotangent graph: y = cot x

18.12
Secant graph: y = sec x

18.13
Cosecant graph: y = csc x

18.14
Solving trigonometric equations involving multiple angles

18.15
Solving trigonometric equations using pythagorean identities

18.16
Solving trigonometric equations using sum and difference identities

18.17
Solving trigonometric equations using doubleangle identities

18.18
Use sine ratio to calculate angles and side (Sin = $\frac{o}{h}$ )

18.19
Using cosine ratio to calculate angles and side (Cos = $\frac{a}{h}$ )

18.20
Use tangent ratio to calculate angles and side (Tan = $\frac{o}{a}$)

18.21
Combination of SohCahToa questions

18.22
Pythagorean theorem

18.23
Unit circle

18.24
Sine law

18.25
Cosine law

18.26
Word problems relating ladder in trigonometry

18.27
Word problems relating guy wire in trigonometry

18.28
Other word problems relating angles in trigonometry
Don't just watch, practice makes perfect.
Solving trigonometric equations using doubleangle identities
Basic concepts:
 Reference angle
 Find the exact value of trigonometric ratios
 ASTC rule in trigonometry (All Students Take Calculus)
 Doubleangle identities
Related concepts:
 Derivative of trigonometric functions
Lessons

1.
Utilizing "DoubleAngle Identities" to solve:
Solving trigonometric equations using doubleangle identities
Don't just watch, practice makes perfect.
We have 1040 practice questions in Algebra 2 for you to work through.