wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The value of k, for which
(cos x + sin x)2 + k sin x cos x - 1 = 0 is an identity, is

A
-1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B

(b) Given, (cos x + sin x)2 + k sin x cos x - 1 = 0, x
cos2x +sin2x + 2cos x sin x + k sin x cos x - 1 = 0, x
(k + 2)cos x sin x = 0, x
k = -2


flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Integration
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon