Question
If tan A = 1 and tan B = √ 3, what is the value of cos
A . cos B - sin A . sin B?Solution
Given, tan A = 1 ⇒ A = 45° Also given, tan B = √ 3 ⇒ B = 60° ∴ cos A . cos B - sin A . sin B = cos 45° . cos 60° - sin 45° . sin 60° = 1/ √ 2 * 1/2 - 1/ √ 2 . √ 3/2 = (1 - √ 3)/2 √ 2
A bag contains 16 black and 18 white balls. One ball is drawn at random. What is the probability that the ball drawn is white?
Find the simplified value of the given expression:
18 × 3 ÷ 6 + 24 ÷ 4 of 2 − 60 ÷ 2 of 3 + 18 × 5 ÷ 9.
...Two dice are thrown simultaneously. Find the probability that sum of the numbers appeared on both the dice is at least 7.
There are 72 balls in a box, consisting of Black, White, and Purple balls. The chance of choosing a black ball is (1/6), and the number of purple balls ...
Out of 6 white marbles, 3 blue marbles, in how many ways we select one or more marbles?
One five letter word is to be formed taking all letters – U, Z, M, O and Q. What is the probability that this formed word will contain all vowels tog...
A box contains 6 blue shirts, 7 yellow shirts and 9 pink shirts. In how many ways can 4 shirts be drawn from the box, if at least one blue shirt, one ye...
A bag contains 4 white balls, 9 red balls, and 5 green balls. Two balls are drawn at random. Find the probability that the two balls are red.
There are three boxes ‘A’, ‘B’ and ‘C’. Box ‘A’ contains 6 black and 12 white cubes, box ‘B’ contains 6black, and 8 white cubes and ...
A bag contains 3 blue, 2 green, and 5 black pens. If five pens are selected randomly, what is the probability that exactly two are green and three are b...
Relevant for Exams:
Hey, Don't leave. If you have any queries regarding any exam let us know here.
