✏️ Trigonometric Identities: Practice A (F-TF.C.8)
Paginepagineapp.comProve and use the Pythagorean identity sin²θ + cos²θ = 1. Solve each problem.
1. sin θ = 5/13, θ in quadrant II. cos θ = ___, tan θ = ___
2. sin θ = 7/25, θ in quadrant II. cos θ = ___, tan θ = ___
3. sin θ = 5/13, θ in quadrant I. cos θ = ___, tan θ = ___
4. sin θ = 7/25, θ in quadrant I. cos θ = ___, tan θ = ___
5. sin θ = 8/17, θ in quadrant II. cos θ = ___, tan θ = ___
6. sin θ = 3/5, θ in quadrant I. cos θ = ___, tan θ = ___
7. sin θ = 8/17, θ in quadrant I. cos θ = ___, tan θ = ___
8. sin θ = 3/5, θ in quadrant II. cos θ = ___, tan θ = ___
9. sin θ = 8/17, θ in quadrant I. cos θ = ___, tan θ = ___
10. sin θ = 7/25, θ in quadrant II. cos θ = ___, tan θ = ___
11. sin θ = 5/13, θ in quadrant I. cos θ = ___, tan θ = ___
12. sin θ = 7/25, θ in quadrant II. cos θ = ___, tan θ = ___
Answer key: 1) cos θ = −12/13, tan θ = −5/12 · 2) cos θ = −24/25, tan θ = −7/24 · 3) cos θ = 12/13, tan θ = 5/12 · 4) cos θ = 24/25, tan θ = 7/24 · 5) cos θ = −15/17, tan θ = −8/15 · 6) cos θ = 4/5, tan θ = 3/4 · 7) cos θ = 15/17, tan θ = 8/15 · 8) cos θ = −4/5, tan θ = −3/4 · 9) cos θ = 15/17, tan θ = 8/15 · 10) cos θ = −24/25, tan θ = −7/24 · 11) cos θ = 12/13, tan θ = 5/12 · 12) cos θ = −24/25, tan θ = −7/24
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Worksheets › Grade 12 Math (Precalculus & Statistics) › Trigonometric Identities › Trigonometric Identities
Grade 12 (ages 17–18)Numbers & mathsFree printable PDF
About this grade 12 worksheet
Free Grade 12 Precalculus & Statistics math worksheet (Common Core F-TF.C.8): trigonometric identities — twelve practice problems, with answer key. Skill: Prove and use the Pythagorean identity sin²θ + cos²θ = 1. Level: Grade 12 — also suits Year 13 (UK).
For teachers: skills & standards
- CCSS F-TF.C.8: Prove and use the Pythagorean identity sin²θ + cos²θ = 1
- Works as a morning-work page, a centre/station activity, homework or an early-finisher task.
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It is designed for Grade 12 (ages 17–18), but use it with any child who is ready.
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Prove and use the Pythagorean identity sin²θ + cos²θ = 1.
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More “Trigonometric Identities” printables (f-tf.c.8: prove and use the pythagorean identity sin²θ + cos²θ = 1)
Trigonometric Identities: Practice B (F-TF.C.8) · Trigonometric Identities: Mixed Practice & Reasoning (F-TF.C.8) · Trigonometric Identities: Show Your Thinking (F-TF.C.8) · Trigonometric Identities: Quick Check (F-TF.C.8)
All 5 trigonometric identities sheets → · Grade 12 Math (Precalculus & Statistics): all 10 skills → · All Common Core grades
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