In this case, we have: `X_L- X_C= 8 - 11 = -3\ Ω`

So `Z = 4 - 3j\ Ω` in rectangular form.

Now to express it in polar form:

Using calculator, we find `r = 5` and ` θ = -36.87^@`.

[NOTE: We usually express the phase angle (when voltage lags
the current) using a **negative value**, rather than the
equivalent positive value `323.13^@`.]

So `Z = 5 ∠ -36.87^@\ Ω`

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