prove.
sin [(pi over 4)+x] + sin [(pi over 4)-x] = sqrt{2} cosx

Question

myininaya · Answer

i think expanding both of those things might help

anonymous · Answer

use ... sin(a=b)= sin(a)cos(b) +cos(a)sin(b)
and     sin(a-b)= sin(a)cos(b) -cos(a)sin(b)

anonymous · Answer

all i know is that i will have to use addition indentities.

myininaya · Answer

$$[\sin(\frac{\pi}{4})\cos(x)+\sin(x)\cos(\frac{\pi}{4})]+[\sin(\frac{\pi}{4})\cos(x)-\sin(x)\cos(\frac{\pi}{4})]$$

myininaya · Answer

$$\frac{\sqrt{2}}{2} \cos(x)+\sin(x) \frac{\sqrt{2}}{2}+\frac{\sqrt{2}}{2}\cos(x)-\sin(x)\frac{\sqrt{2}}{2}$$

myininaya · Answer

combine like terms and you will be done

anonymous · Answer

its 2sin(a)cos(b)....now plug valus.....(2/$$\sqrt{2}$$ ) sinx

anonymous · Answer

$$\sqrt{2}$$ sin x

anonymous · Answer

you rock myininaya!!! 
thank you so much!!! 

and i appreciate your work and help Sam_unleashed! 
:)