Question

dy
Find the value of
dx
when
y = cos (x - y)​

Answer 1

Answer:

- sin(x - y)

Step-by-step explanation:

=> d(cos(x-y))/dx

=> d(cosx.cosy + sinx.siny)/dx

=> d(cosx.cosy)/dx + d(sinx.siny)/dx

=> cosy.d(cosx)/dx + siny.d(sinx)/dx

=> cosy(-sinx) + siny(cosx)

=> - sinx.cosy + siny.cosx

=> - [ sinx.cosy - siny.cosx]

=> - [sin(x - y)]

=> - sin(x - y)