Q. Prove that: 8cos(pi/7).sin(3*pi/14).sin(pi/14) = 1

SUBSCRIBE TO OUR NEWSLETTER
You May Also Like
11. Find the number of geometric means inserted between 1 and 243 in which the ratio of the first mean to the last mean is 1:27. Soln: ...
Calculate value of sin18 without using calculator. Soln: ...
Q. The angle of elevation of an aeroplane from a point on the ground is 450. After 15 seconds of flight the angle of elevation changes to 300. If the aeroplane is flying horizontally at a height of 4000m in the same direction, find the speed of aeroplane. Soln: ...
Q. Evaluate: Cos6° × sin24° × cos72° Soln: Cos6° × sin24° × cos72° = (1/2) * 2 Cos6° × sin24° × cos72° = (1/2) [sin(6+24) – sin(6-24)] * cos72 = (1/2) ...
Q. Prove that: sec2A+tan2A=tan(45+A) L.H.S. = 1 / cos(2a) + sin(2a) / cos(2a) = (1 + sin(2a)) / (cos(2a)) = (sin^2(a) + cos^2(a) + 2 * sin(a) * cos(a)) / (cos^2(a) - s ...