# Tag Archives: RD Sharma Class-11

Question 1(i). Find the coordinates of the centre and radius of the circle x2 + y2 + 6x – 8y – 24 = 0. Solution:… Read More
Question 31. A bag contains 5 red, 6 white and 7 black balls. Two balls are drawn at random. Find the probability that both balls… Read More
Question 16. A bag contains 7 white, 5 black, and 4 red balls. If two balls are drawn at random, find the probability that: (i)… Read More
Question 1. Which of the following cannot be valid assignment of probability for elementary events of outcomes of sample space S={w1,  w2, w3, w4, w5,… Read More
Question 11. If cosec A + sec A = cosec B + sec B, prove that tan A tan B =. Solution: We have, cosec… Read More
Question 1. Express each of the following as the product of sines and cosines: (i) sin 12θ + sin 4θ Solution: We know, sin A… Read More
Question 20. limx→1[(1 + cosπx)/(1 – x)2] Solution: We have, limx→1[(1 + cosπx)/(1 – x)2] Here, x→1, h→0 = Limh→0[{1 + cosπ(1 + h)}/{1 –… Read More
Question 1: Sketch the following graphs: (i) y = cos (x+) Solution: To obtain this graph y-0 = cos (x+), Shifting the origin at , we… Read More
Sketch the graphs of the following functions: Question 1: y = sin2 x Solution: As we know that, y = sin2 x =  On shifting… Read More
Question 1: Find the equation of the straight lines passing through the origin and making an angle of 45° with the straight line √3x+y =… Read More
Question 1. Find the equation of the circle, the end points of whose diameter are (2, -3) and (-2, 4). Find its radius and centre.… Read More
Prove the following identities:  Question 1. √[(1 – cos2x)/(1 + cos2x)] = tanx Solution: Let us solve LHS, = √[(1 – cos2x)/(1 + cos2x)] As… Read More
Question 1. limx→π/2[π/2 – x].tanx Solution: We have, limx→π/2[π/2 – x].tanx Let us considered, y = [π/2 – x] Here, x→π/2, y→0 = limy→0[y.tan(π/2 –… Read More
Question 30(i). If 0 ≤ x≤ π and x lies in the 2nd quadrant such that sinx = 1/4, Find the values of cos(x/2), sin(x/2),… Read More
Prove the following identities:  Question 16. cos2 (π/4 – x) – sin2 (π/4 – x) = sin 2x Solution: Let us solve LHS, = cos2… Read More