Practicing Success
If $\frac{1}{cosec \theta + 1} + \frac{1}{cosec \theta -1} = 2 \sec \theta, 0^\circ < \theta < 90^\circ$, then the value of $\frac{\tan \theta + 2 \sec \theta}{cosec \theta}$ is: |
$\frac{4+\sqrt{3}}{2}$ $\frac{2+\sqrt{3}}{2}$ $\frac{4+\sqrt{2}}{2}$ $\frac{2+\sqrt{2}}{2}$ |
$\frac{4+\sqrt{2}}{2}$ |
\(\frac{1}{cosecθ + 1 }\) + \(\frac{1}{cosecθ - 1 }\) = 2secθ \(\frac{cosecθ - 1 + cosecθ + 1}{cosec²θ - 1² }\) = 2secθ { using , cosec²θ - 1² = cot²θ } 2cosecθ = 2secθ cotθ = 1 { we know, cot45º = 1 } So, θ = 45º Now, \(\frac{tanθ + 2secθ}{cosecθ}\) = \(\frac{tan45º + 2sec45º}{cosec45º}\) = \(\frac{1 + 2√2}{ √2 }\) = \(\frac{4+ √2}{ 2 }\) |