So, I wasn't there when they went through this in class, and even though I've looked on the internet, I have no idea what to do.
Help would be greatly appreciated. (:
Find the modulus of the following complex numbers:
3+5i
6-10i
7-8i
(3+5i)^3
So, I wasn't there when they went through this in class, and even though I've looked on the internet, I have no idea what to do.
Help would be greatly appreciated. (:
Find the modulus of the following complex numbers:
3+5i
6-10i
7-8i
(3+5i)^3
the modulus of a complex number $\displaystyle z = x + iy$ is given by: $\displaystyle |z| = \sqrt{x^2 + y^2}$
example, find the modulus of $\displaystyle z = 3 + i \sqrt{7}$
$\displaystyle |z| = \sqrt{3^2 + (\sqrt{7})^2} = \sqrt{16} = 4$
that's it
another rule: $\displaystyle |z^n| = |z|^n$(3+5i)^3
example, find the modulus of $\displaystyle (3 + i \sqrt{7})^3
$
Let $\displaystyle z = 3 + i \sqrt{7}$
we want $\displaystyle |z^3|$
now, $\displaystyle |z^3| = |z|^3 = 4^3 = 64$
now try your problems