Question

Tan8 x - tan6x- tan2 = tan8x tan 6x tan2x

prove it?

Answer 1

6x+2x=8x
tan(6x+2x)=tan8x
tan6x+tan2x/1-tan6xtan2x=tan8x
tan6x+tan2x=tan8x-tan8xtan6xtan2x
tan8x-tan6x-tan2x=tan8xtan6xtan2x

Answer 2

Answer:

Step-by-step explanation:

Let $6x+2x=8x$

Taking tan on both sides, and then using the formula $tan(A+B)=\frac{tanA+tanB}{1-tanAtanB}$,wehave

$tan(6x+2x)=tan8x$

$\frac{tan6x+tan2x}{1-tan6xtan2x}$=tan8x

$tan6x+tan2x=tan8x-tan8xtan6xtan2x$

$tan8xtan6xtan2x=tan8x-tan6x-tan2x$

Hence proved.