Question

Find dy/dx by implicit differentiation:
cos(x−y)=−4xe^x

Answer 1

-sin(x-y)(1-y') = -4e^x - 4xe^x
sin(x-y)y' = sin(x-y)-4e^x(1+x)

y' = (sin(x-y)-4e^x(1+x))/sin(x-y)
= 1 - 4 e^x (1+x) csc(x-y)