convert the complex number -8+5i into the form re^itheta

does it mean the same as polar form so i will get

9.4<2.59

so 9.4cos 2.59 +9.4 sin 2.59 =-8+5i

or is it asking for something else any help would be very greatful

also i have a couple of these and also dont understand

evaluate;

3e^2i

e^iPi

and a couple more with basically the same things but dont know what to do thank you for any help cheers