Please solve the given following question :

If $x = \tan \frac{π}{18}$ then 3x⁶– 27x⁴ + 33x² is equal to-
(A) 1
(B) 2
(C) $3 \sqrt{3}$
(D) $\frac{1}{3}$

Question

Please solve the given following question :

If x = tan π 18 then 3x6 – 27x4 +
33x2 is equal to-
(A) 1
(B) 2
(C) 3 3
(D) 1 3

Zuhaib Ul Zamann · Accepted Answer

Dear student,
We know tan3t=3tant-tan3t1-3tan2tPut t=π1813=3tanπ18-tan3π181-3tan2π18Squaring both sides we get13=9tan2π18+tan6π18-6tan4π181+9tan4π18-6tan2π181+9tan4π18-6tan2π18=27tan2π18+3tan6π18-18tan4π183tan6π18-27tan4π18+33tan2π18=1Option A is correctRegards

Please solve the given following question : If x = tan π 18 then 3x6 – 27x4 + 33x2 is equal to- (A) 1 (B) 2 (C) 3 3 (D) 1 3

Please solve the given following question :

If $x = \tan \frac{π}{18}$ then 3x⁶– 27x⁴ + 33x² is equal to-
(A) 1
(B) 2
(C) $3 \sqrt{3}$
(D) $\frac{1}{3}$