Ask your own question, for FREE!
Mathematics 15 Online
OpenStudy (anonymous):

Find all solutions to the equation: cos x = -(1/2)

OpenStudy (sidsiddhartha):

u wanna solve it right?

OpenStudy (sidsiddhartha):

first tell me which value of cos(theta) is -1/2

OpenStudy (anonymous):

@sidsiddhartha find all solutions, yeah.. hold on let me show you the answer choices

OpenStudy (anonymous):

60 deg or pi/3?

OpenStudy (sidsiddhartha):

no, do u know which value of cos(theta) in angle produces -1/2?

OpenStudy (anonymous):

OpenStudy (anonymous):

thats what i thought it was

OpenStudy (anonymous):

bc its negative its in the 2nd quadrant i thought, and then the theta is across from 60 @sidsiddhartha

OpenStudy (sidsiddhartha):

Negative cosines happen only in the second and third quadrants.

OpenStudy (sidsiddhartha):

right?

OpenStudy (anonymous):

yeah, its in the second right?

OpenStudy (sidsiddhartha):

so first of all cos(180-60)=cos120=-1/2 ok?

OpenStudy (anonymous):

|dw:1415476761716:dw|

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!