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Mathematics Worksheet
🔗 Trigonometric Identities
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Use the Pythagorean identity sin2θ + cos2θ = 1.Use the quotient identity tan θ = sin θ/cos θ.Use the reciprocal identities.Simplify trigonometric expressions.📚 Quick Recap
Trigonometric identities are equations that are always true for every valid angle — powerful tools for simplifying expressions and solving trig equations.
🧠 Section A · Concept Check ● BEGINNER 4 × 1 = 4
1If cos θ = 0.6 (Quadrant I), then sin θ =:
2tan θ · cos θ simplifies to:
3tan θ = sin θ divided by:
4csc θ =:
🧮 Section B · Problem Solving ● INTERMEDIATE 2 + 3×3 = 11
5The Pythagorean identity is sin2θ + cos2θ = .
6tan θ = sin θ / .
7If cos θ = 0.6, find sin θ (Quadrant I).
8Simplify tan θ · cos θ.
9If tan θ = 0.75 and cos θ = 0.8, find sin θ using the quotient identity.
🚀 Section C · Challenge ● CHALLENGE 5
10If sin θ = 0.28, find csc θ (approximately).
💭 Reflection — the most useful thing I learned:
A ___/4 B ___/11 C ___/5 Total ___/20
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1-A 2-A 3-A 4-A | 5 1 6 cos θ 7 = 0.8 8 = sin θ 9 = 0.6 (sin = tan · cos) | 10 = 1/0.28 ≈ 3.57