Relating sine, cosine and tangent
Mathematics · Grade 10 · about 40 minutes
tan theta is sin theta over cos theta, and sin squared plus cos squared is 1, both from the same right-angled triangle.
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Other lessons in this sub-strand
- The three ratios
- Finding angles, elevation and depression
- Labelling from either acute angle
- Calculators and mathematical tables
- When the unknown is the denominator
- Sine and cosine of complementary angles
- Relating sine, cosine and tangent
- Special angle 45 degrees
- Special angles 30 and 60 degrees
- Special angle 90 degrees and the exact-value table
- Inverse ratios in practice
- Solving a complete right-angled triangle
- Height from two positions
- Depression from a height
- A clinometer and trigonometry around us