(a) find all points where the function f(z) = (x^2+y^2-2y)+i(2x-2xy) is differentiable, and compute the derivative at those points.

The given function is differentiable at y = 1.

At y = 1, f'(z)  = 0

Step-by-step explanation:

As per the given question,

Let z = x + i y

Suppose,

On computing the partial derivatives of u and v as:

And

According to the Cauchy-Riemann equations

Now,

Therefore,

holds only.

This means,

2y - 2 = 0

⇒ y = 1

Therefore f(z) has a chance of being differentiable only at y =1.

Now we can compute the derivative

At y = 1

f'(z) = 0

Hence, the required derivative at y = 1 ,  f'(z)  = 0

answer: the value should be used for i in the formula of calculation the monthly payment , the interest rate per period is 0.85.

step-by-step explanation:

the given rate of interest i= 85%

in calculating the monthly payment for a loan with an interest rate compounded monthly, the value of the interest rate per period we use in the formula must be in decimal form.

to convert it in decimal, we divide it by 100, we get

hence, the value should be used for i in the formula of calculation the monthly payment , the interest rate per period is 0.85.

i am unable to solve this problem

step-by-step explanation: