# Category Archives: Class 11

Evaluate the following limits: Question 1.  Solution: We know if  such that  exists, then  We have, =  =  = ex Question 2.  Solution: We have, =  = … Read More
Question 1. Express each of the following as the sum or difference of sines and cosines: (i) 2 sin 3θ cos θ Solution: By using… Read More
Question 11. In any ∆ABC, prove the following: a cos A + b cos B + c cos C = 2b sin A sin C.… Read More
Question 1. Find the equation of a line passing through the point (2, 3) and parallel to the line 3x – 4y + 5 =… Read More
Sum the following series to n terms: Question 1. 3 + 5 + 9 + 15 + 23 + . . . . n terms… Read More
Question 1. Sketch the following graphs: (i) y = 2 sin 2x Solution: To obtain this graph y = 2 sin 2x, First we draw… Read More
Question 1. Find the general solution of following equations: (i) sin θ = 1/2 Solution: We are given, => sin θ = 1/2 => sin… Read More
Prove that: Question 1.  sin2 72o – sin2 60o = (√5 – 1)/8 Solution: We have, L.H.S. = sin2 72o – sin2 60o = sin2… Read More
Question 11. A rail road curve is to be laid out on a circle. What radius should be used if the track is to change… Read More
Question 1. Find the degree measure corresponding to the following radian measures using π = 22/7: (i) 9π/5 Solution: We know that π radians =… Read More
Prove that: Question 1. sin 5θ = 5sin θ – 20 sin3 θ + 16 sin5 θ Solution: We have, L.H.S. = sin 5θ =… Read More
Conic sections are curves generated when a plane intersects a right circular cone at different angles. Conic section has the definition in its name, It… Read More
Question 1. In a ∆ABC, if a = 5, b = 6 and C = 60o, show that its area is (15√3)/2 sq. units. Solution:… Read More
Question 17. If the 4th, 10th and 16th terms of a G.P. are x, y, and z, respectively. Prove that x, y, z are in… Read More
Question 1.  Find the 20th and nth terms of the G.P 5/2, 5/4, 5/8, … Solution: According to the question G.P: 5/2, 5/4, 5/8, …… Read More