How do you evaluate #y=sin(x + (pi/2) )#? Trigonometry Graphing Trigonometric Functions Translating Sine and Cosine Functions 1 Answer ali ergin Aug 1, 2016 #y=cos x# Explanation: #y=sin(x+(pi/2)) ?# #sin(a+b)=sin a*cos b+cos a*sin b# #y=sin x*cos (pi/2)+cos x*sin(pi/2)# #"plug "sin (pi/2)=1" ; "cos(pi/2)=0# #y=sin x*0 +cos x*1# #y=0+cos x# #y=cos x# Answer link Related questions How do you graph sine and cosine functions when it is translated? How do you graph #y=sin ( x -frac{\pi}{2} )#? How do you draw a sketch of #y = 1 + cos (x - pi)# How do you shift and graph #y=-3+sinx#? How do you graph #y=3sin(1/3x+ pi/2)-2#? How do you graph #1/2sin(x-pi)#? How do you graph #-sinx+2#? How do you graph #y=3sin(1/2)x#? How do you graph #y=-2cos((pix)/3)#? How do you graph #y = (1/2)sin(x - pi)#? See all questions in Translating Sine and Cosine Functions Impact of this question 3946 views around the world You can reuse this answer Creative Commons License