Q. 235.0( 1 Vote )


Using the formula tan 2θ = ,obtain the value of tan 15°.

Answer :


tan 2θ =
Putting θ = 15°,
tan 30° =

1/√3 =

1 tan 2 15° = 2√3(tan 15°)

tan 2 15° + 2√3(tan 15°) – 1= 0

tan 15 ° =

Since, tan 15° is positive as it is lying in first quadrant, and -√3 – 2<0, therefore it can’t be the value of tan 15°.

tan 15 ° = 2 - 3.

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