Saved Bookmarks
| 1. |
tan 0 ,1-cot θcot 0+1-tan θFig. 3Prove that:-1+sec θ cosech1+tan 0 + cot.30, |
|
Answer» GIVEN:- tanθ/(1 - cotθ) + cotθ/(1 - tanθ) => tanθ/(1 - 1/tanθ) + (1/tanθ)/(1 - tanθ) => tan²θ/(tanθ - 1) - 1/tanθ(tanθ - 1) => 1/(tanθ - 1) { tan²θ - 1/tanθ } => 1/(tanθ - 1) { (tan³θ - 1)/tanθ) [as, a³ - b³ = (a - b)(a² + b² + ab) => {(tanθ - 1)(tan²θ + 1 + tanθ)}/{(tanθ - 1)(tanθ)} => tanθ + cotθ + 1 => sinθ/cosθ + cosθ/sinθ + 1 => (sin²θ + cos²θ)/sinθ . cosθ + 1 => 1/sinθ . cosθ + 1 => cosecθ . secθ + 1 |
|