SOLUTION: I wanted to know how do you solve the question: if cos Ө = -1/3 using trig. identities find the exact value of sin(Ө-pi/2) I am extremely lost, thank you in advance

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Question 770441: I wanted to know how do you solve the question:
if cos Ө = -1/3 using trig. identities find the exact value of sin(Ө-pi/2)
I am extremely lost, thank you in advance!

Answer by lwsshak3(11628)   (Show Source): You can put this solution on YOUR website!
wanted to know how do you solve the question:
if cos Ө = -1/3 using trig. identities find the exact value of sin(Ө-pi/2)
***
use sin addition formula:
sin(s-t)=sin s cos t-cos s sin t
sin( Ө-π/2)=sin Ө*cos(π/2)-cos Ө*sin(π/2)
=sin Ө*0-cos Ө*1
=-cos Ө=1/3
sin(Ө-pi/2) =1/3

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