PLEASE HELP

what's x
cos(x+pi)-sin(x-pi)=0

please show work​

sin(x+pi)=-sin(x)=sin(-x)=cos(pi/2)

cos (x+pi)=-cos(x)

So according to the question:

cos(pi/2 +x)=cos(x)

Using the solution of cos, obtain:

(pi/2) + x = 2pi +- (x)

case#1: (pi/2) + x = 2pi + (x)

But here, the value of x is canceled, just

case#2: (pi/2) + x = 2pi - (x)

answer>>>>>>>>> x=pi-pi/4

a = 11 : 4

b = 38

c = 1 for every 6

b.my answer is b.

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