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Ex 8.2, 1 (i) - Chapter 8 Class 10 Introduction to Trignometry
Last updated at April 16, 2024 by Teachoo
Trignometric ratios of Specific Angles - Evaluating
Chapter 8 Class 10 Introduction to Trignometry
Concept wise
- Finding sin cos tan
- Finding sin cos when sides of a triangle are given
- Finding ratios when other ratios are given
- Finding values of expressions
- Proving
-
Trignometric ratios of Specific Angles - Evaluating
- Trignometric ratios of complementry angles
- Expressing ratios in other ratios
- Evaluating using Trignometric Identities
Transcript
Ex 8.2, 1 Evaluate the following : (i) sin 60° cos 30° + sin 30° cos 60° We know that, sin 60° = √3/2 cos 30° = √3/2 sin 30° = 1/2 cos 60° = 1/2 Putting all values sin 60° cos 30° + sin 30° cos 60° = (√𝟑/𝟐)×(√𝟑/𝟐)+(𝟏/𝟐)×(𝟏/𝟐) = (√3 × √3)/(2 × 2)+1/(2 × 2) = 𝟑/𝟒 + 𝟏/𝟒 = (3 + 1)/4 = 4/4 = 1 Hence, sin 60° cos 30° + sin 30° cos 60° = 1
