SOLUTION: If sin(x-pi/2)=0.2, what's the cos x? A)0.8 B)0.98 C)-0.2 D)0.2

Algebra ->  Finance -> SOLUTION: If sin(x-pi/2)=0.2, what's the cos x? A)0.8 B)0.98 C)-0.2 D)0.2      Log On


   

Question 1089348: If sin(x-pi/2)=0.2, what's the cos x?
A)0.8
B)0.98
C)-0.2
D)0.2
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

sin%28x-pi%2F2%29=0.2
sin+%28x-pi%2F2%29=sin%28x%29cos%28pi%2F2%29-cos%28x%29sin%28pi%2F2%29
sin%28x%29cos%28pi%2F2%29-cos%28x%29sin%28pi%2F2%29=0.2.............cos%28pi%2F2%29=0, sin%28pi%2F2%29=1
sin%28x%29%2A0+-cos%28x%29%2A1=0.2
-cos%28x%29=0.2
cos%28x%29=-0.2

answer is: C)-0.2