Question

Find the product of the complex numbers. Leave the answer in polar form.
Z1=5(cos20º+i sin20º)
Z2= 4(cos10º + i sin10º)

Answer 1

Can you write these in exponential form?

Answer 2

It's a well-known identity:\[\large\cos(\theta) + i\sin (\theta) =e^{i\theta}\]

Answer 3

i got 20e^(i 30º) = 20(cos 30º + i sin 30º)

Answer 4

Not well known enough, apparently ^_^

To multiply complex numbers in their polar form,
then multiply their moduli, and add their arguments...
that's the gist of it.

Answer 5

@Y$G_Jay Where is 30 degrees?