Prove that cos340º.cos40°+sin 200° sin 140º =
Answers
Answered by
1
Answer:
helllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
Answered by
2
Answer:
cos340°.cos40°+ sin200°.sin140°
= cos20°.cos40° + (-sin20°).sin40°
= cos20°cos40° - sin20°sin40°
= cos(20°+40°)
= cos60°
= 1/2
= 0.5
Please mark me as brainlist
Similar questions