Find dy/dx by implicit differentiation for ycos(x)=xcos(y)

dy/dx = (cos y + y sin x) / (cos x + x sin y)

Step-by-step explanation:

y cos x = x cos y

y (-sin x) + dy/dx cos x = x (-sin y dy/dx) + cos y

-y sin x + dy/dx cos x = -x sin y dy/dx + cos y

dy/dx (cos x + x sin y) = cos y + y sin x

dy/dx = (cos y + y sin x) / (cos x + x sin y)

answer: 25.4 units

step-by-step explanation: radius = 12.7 units

diameter = twice the radius

diameter = 12.7 x 2

= 25.4

answer: $201

step-by-step explanation: to get the answer, you first get 3 nieces that he sold and multiply it by 67 and get $201, so he earned $201 selling his nieces.