CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The value of 13k=11sin(π4+(k1)π6)sin(π4+kπ6) is equal to

A
33
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
2(33)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
2(31)
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
2(2+3)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 2(31)
13k=1sin[(π4+kπ6)(π4+(k1)π6)]sinπ6(sin(π4+kπ6)sin(π4+(k1)π6))=213k=1(cot(π4+(k1)π6)cot(π4+kπ6))
using compound angle formula.
=2(cotπ4cot(π4+13π6))
=2(1cot(29π12))
=2(1cot(5π12))
=2(1(23))
=2(2+3)
=2(31)

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Pythagorean Identities
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon