1.
tan⁡(π4+12cos⁡−1x)+tan⁡(π4−12cos⁡−1x)\tan\left(\dfrac{\pi}{4} + \dfrac{1}{2}\cos^{-1} x\right) + \tan\left(\dfrac{\pi}{4} - \dfrac{1}{2}\cos^{-1} x\right), x≠0x \neq 0, is equal to