If x = tan 40°, then the value of 2 tan 50° will be :

$\frac{1}{2X}$ 2X $\frac{1}{X}$ $\frac{2}{X}$

$\frac{2}{X}$

tanA = cotB  then A + B = 90° Now, 2tan50° = 2 tan ( 90° - 50° ) = 2cot 40° = 2 ×  \(\frac{1  }{x}\) =  \(\frac{2 }{x}\)