Question 13 - CBSE Class 10 Sample Paper for 2022 Boards - Maths Standard [MCQ] - Solutions of Sample Papers for Class 10 Boards

Last updated at Sept. 6, 2021 by Teachoo

In ∆ABC right angled at B, if tan A = √3, then cos A cos C - sin A sin C =

(a) 1 (b) 0 (c) 1 (d) √3 /2

This question is inspired from Ex 8.1, 9 - Chapter 8 Class 10 - Introduction to Trignometry

This video is only available for Teachoo black users

Subscribe Now

Introducing your new favourite teacher - Teachoo Black, at only ₹83 per month

Join Teachoo Black

Next: Question 14 →

Transcript

Question 13 In ∆ABC right angled at B, if tan A = √3, then cos A cos C - sin A sin C = (a) 1 (b) 0 (c) 1 (d) √3 /2 Given, tan A = √3 ∴ ∠ A = 60° Now, In Δ ABC By Angle sum property ∠ A + ∠ B + ∠ C = 180° 60° + 90° + ∠ C = 180° 150° + ∠ C = 180° ∠ C = 180° − 150° ∠ C = 30° Now, cos A cos C − sin A sin C = cos 60° cos 30° − sin 60° sin 30° = 1/2 × √3/2 − √3/2 × 1/2 = 0 So, the correct answer is (b)

Made by

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths and Science at Teachoo.

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Popular