Special angle 90 degrees and the exact-value table
Mathematics · Grade 10 · about 40 minutes
sin 90 is 1, cos 90 is 0, tan 90 is undefined, and the five-angle table is the one to know by heart.
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- 8 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
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