# Tag Archives: RD Sharma Class-11

Question 1. Find the 11th term from the beginning and the 11th term from the end in the expansion of (2x – 1/x2)25. Solution: We… Read More
Question 16: In △ABC, prove the following: a2 (cos2 B – cos2 C) + b(cos2 C – cos2 A) + c(cos2 A – cos2 B)… Read More
Question 1: If in △ABC, ∠A=45°, ∠B=60°, and ∠C=75°, find the ratio of its sides. Solution: According to the sine rule Hence, we get Using… Read More
Question 1. The vertices of the triangle are A(5, 4, 6), B(1, -1, 3), and C(4, 3, 2). The internal bisector of angle A meets… Read More
Question 1. Using binomial theorem, write down the expressions of the following: (i) (2x + 3y)5 Solution: Using binomial theorem, we have, (2x + 3y)5… Read More
Question 21. Differentiate (2x2 – 3) sin x with respect to x. Solution: We have, => y = (2x2 – 3) sin x On differentiating… Read More
Question 11. Differentiate (x sin x + cos x) (x cos x − sin x) with respect to x. Solution: We have, => y =… Read More
Question 1. Differentiate x3 sin x with respect to x. Solution: We have,  => y = x3 sin x On differentiating both sides with respect… Read More
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