Practice Complementary Angle Theorem (2.3) - Theorems in Geometry & Trigonometry

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9 questions

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6 sample questions

Question 1.
What is the value of cos(90° - 30°)?
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Remember that cos(90° - θ) = sin θ.
Question 2.
If sin θ = 0.6, what is cos(90° - θ)?
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Use the complementary angle theorem.
3Question 3.
What is sin(90° – θ) equal to?
- cos θ
- tan θ
- cot θ
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Think about how sine and cosine relate with complementary angles.
4Question 4.
True or False: tan(90° – θ) = cot θ.
- True
- False
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Recall the definition of tangent and cotangent.
Question 5.
If sin θ = 4/5, calculate cos(90° – θ) and tan(90° – θ).
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Use the relationship to find additional trig values.
Question 6.
Prove the identity sin² θ + cos² θ = 1 using the complementary angle theorem.
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Think about how sine and cosine relate to one another when squared.

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