SOLUTION: find the exact value of cos 195 degrees + cos 105 degrees
Algebra.Com
Question 594726: find the exact value of cos 195 degrees + cos 105 degrees
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
find the exact value of cos 195 degrees + cos 105 degrees
**
Sum to product formula:
cos s + cos t=2cos(s+t)/2*cos(s-t)/2
..
cos 195+cos 105=2cos(195+105)/2*(cos)195-95)/2
=2cos(300/2)*cos(90/2)
=2cos(150)*cos(45)
=2*-√3/2*√2/2
=-√6/2 ≈-1.224
RELATED QUESTIONS
find the exact value of cos 105 degrees WITHOUT USING TABLES OR A CALCULATOR. be sure to... (answered by venugopalramana)
How do you find the exact value of sin 17 degrees cos 28 degrees + cos 17 degrees sin 28... (answered by Fombitz)
find the exact value of the expression
cos 255... (answered by lwsshak3)
find the exact value of cos 225... (answered by lwsshak3)
using sum, difference, half, or double angle formulas and the exact value chart in the... (answered by venugopalramana)
Find the exact value of the expression
tan 195... (answered by arallie)
find exact value
cos (-15... (answered by lwsshak3)
find the value of cos 105 degrees without using a calculator.retain radical... (answered by solver91311)
find the exact values of cos8 degrees cos 38 degrees +sin 8 degrees + sin 38... (answered by sdmmadam@yahoo.com)