Show that COS 20 degree . COS 30 degree . COS 40 degree . COS 80 degree = root3/16
Answers
Answered by
22
cos20.co30.cos40.cos80=root3/16
LHS=1/2 {2cos20.cos40} cos30.cos80
=1/2 {cos60+cos20} cos30.cos80
=1/4cos30.cos80+1/2cos30.co20.cos80
=root3/8.cos80 +root3/8 {2cos20.cos80}
=root3/8.cos80+ root3/8 (cos100+cos60)
=root3/8cos80 +root3/8ccos (180-80)+root3/8cos60
=root3/16=RHS
LHS=1/2 {2cos20.cos40} cos30.cos80
=1/2 {cos60+cos20} cos30.cos80
=1/4cos30.cos80+1/2cos30.co20.cos80
=root3/8.cos80 +root3/8 {2cos20.cos80}
=root3/8.cos80+ root3/8 (cos100+cos60)
=root3/8cos80 +root3/8ccos (180-80)+root3/8cos60
=root3/16=RHS
abhi178:
please mark as brainliest
Answered by
3
Answer:
Step-by-step explanation:
Attachments:


Similar questions
History,
9 months ago
Math,
9 months ago
English,
9 months ago
Social Sciences,
1 year ago
Science,
1 year ago
India Languages,
1 year ago
Chemistry,
1 year ago