\tan20^\circ \tan40^\circ \tan60^\circ \tan80^\circ=

AP ICET 2016 Paper

Question : 126 of 200

Marks: +1, -0

\tan20°\;\tan40°\;\tan60°\;\tan80°=

3
$3/4$
$√3/16$
$√3/4$

Validate

Solution:

We know that
tan A. tan (60 – A). tan (60 + A) = tan 3A
∴ tan 20° . tan 40° . tan 60° . tan 80° = [tan 20° . tan (60° – 20°). tan (60°+ 20°)]. tan 60°

=\tan(3×20°).\tan60°=\tan^{2}60°

=(√3)^2=3

Go to Question:

Prev Question

Next Question