Last updated at Dec. 13, 2024 by Teachoo
Example 6 In Δ ABC, right-angled at B, AB = 5 cm and ∠ ACB = 30° (see Fig.). Determine the lengths of the sides BC and AC. Given AB = 5 cm & ∠ ACB = 30° According to diagram, tan C = (𝑠𝑖𝑑𝑒 𝑜𝑝𝑝𝑜𝑠𝑖𝑡𝑒 𝑡𝑜 𝑎𝑛𝑔𝑙𝑒 𝐶)/(𝑠𝑖𝑑𝑒 𝑎𝑑𝑗𝑎𝑐𝑒𝑛𝑡 𝑡𝑜 𝑎𝑛𝑔𝑙𝑒 𝐶) tan 30° = 𝑨𝑩/𝑩𝑪 1/√3=5/𝐵𝐶 BC = 5 √𝟑 cm sin C = (𝑠𝑖𝑑𝑒 𝑜𝑝𝑝𝑜𝑠𝑖𝑡𝑒 𝑡𝑜 𝑎𝑛𝑔𝑙𝑒 𝐶)/𝐻𝑦𝑝𝑜𝑡𝑒𝑛𝑢𝑠𝑒 sin 30° = 𝑨𝑩/𝑨𝑪 1/2=5/𝐴𝐶 AC = 10 cm Hence, AC = 10 cm & BC = 5 √3 cm
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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo