# Determine the absolute value of each of the following complex numbers: a. z = 3 + 4i b. z = -1 - 2i.

Question
Complex numbers
Determine the absolute value of each of the following complex numbers:
a. z = 3 + 4i
b. z = -1 - 2i.

2021-01-09
a. Given complex number is $$\displaystyle{z}={3}+{4}{i}$$
Absolute value of the given complex number will be:
$$\displaystyle{\left|{z}\right|}=\sqrt{{{3}^{{2}}+{4}^{{2}}}}=\sqrt{{25}}={5}$$
b. Given complex number is z=−1−2i
Absolute value of given complex number will be:
SK|z| = sqrt(1^2+−2^2) = sqrt5ZSK

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