Question

7. tan (45° + x) + tan (45° - x) = 2 sec 2x.​

Answer 1

Step-by-step explanation:

L.H.S =tan(45 + x) + tan(45 - x)

          = $\frac{1+tanx }{1-tanx}+\frac{1-tanx}{1+tanx} = 2 sec2x$

          = $2(\frac{1+tan^{2}x}{1-tan^{2}x})$

          = $\frac{2}{cos2x}$

          = $2sec2x$

          = RHS.