`tanalpha.tan(60^@-alpha).tan(60^@+alpha)=tan3alpha`

tan alpha*tan(60^(@)-alpha)*tan(60^(@)+alpha)=tan3 alpha

Sum the series tan alpha tan (alpha+beta)+tan(alpha+beta)+tan(alpha+2beta)+tan(alpha+2beta)tan(alpha+3beta)+… to n terms

If 4n alpha = pi , then the value of tanalpha*tan2alpha*tan3alpha …..tan(2n-2)alphatan(2n-1)alpha is:

If alpha=(2 pi)/(7), then tan alpha tan2 alpha+tan2 alpha tan4 alpha+tan4 alpha tan alpha

If alpha=(2 pi)/(7) then tan alpha tan^(7)2 alpha+tan2 alpha tan4 alpha+tan2 alpha tan4 alpha=

For alpha=pi/7 which of the following hold(s) good? (a) tanalphatan2alphatan3alpha=tan3alpha-tan2alpha-tanalpha (b)cos e calpha=cos e c2alpha+cos e c4alpha (c)cosalpha-cos2alpha+cos3alpha=1/2 (d)8cosalphacos2alphacos4alpha=1

prove that :tan(alpha)+2tan(2 alpha)+4(tan4 alpha)+8cot(8 alpha)=cot(alpha)

" If "alpha=(2 pi)/(7)" ,and "tan alpha tan2 alpha+tan2 alpha tan4 alpha+tan4 alpha tan alpha=K" .Then "3k^(2)+4k+5=" ."