Part BCSIR NET December 2024cos-of-i-is-cosh-not-sinh

Cos of i is cosh not sinh

Let $f : C \to C$ be the function defined by f(z) = e^((cos(1+i)) sin z). For z = x + iy $\in C$ , write f(z) as u(x, y) + iv(x, y), where u, v are real-valued functions. Which of the following is the value of $(\partial u / \partial x) (0, 0)$ ?

A.0
B.(e + 1/e)(cos 1)/2✓
C.(e − 1/e)(cos 1)/2
D.1

You have the answer. Trap Analysis is why the other three were written.

Not a worked solution repeated four times — the specific reasoning error each wrong option was built to reward.

See pricing

50 are analysed free — try those first.

Cos of i is cosh not sinh

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