Practicing Success
If $\tan^{-1}x+\tan^{-1}y=\frac{π}{4}$, then $\cot^{-1}x+\cot^{-1}y=$ |
$\frac{π}{2}$ $\frac{3π}{4}$ $π$ $\frac{5π}{4}$ |
$\frac{3π}{4}$ |
$\frac{π}{2}-\cot^{-1}x+\frac{π}{2}-\cot^{-1}y=\frac{π}{4}$ $⇒\cot^{-1}x+\cot^{-1}y=\frac{3π}{4}$ |