Well technically, you need the parentheses I added above.

If you look at the trig form of the complex number: , r is the modulus and theta is the argument. Anyway, your modulus is right, but the argument is not. The argument should be pi.to find modulus and arguments of the complex number i need to express it in a+bi form first right? or can i assume b=0? being -8+0i

then |-8+0i| = 8

and arg |-8+0i| = 0

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