Find the modulus and argument of the following complex number and convert them in polar form: `(1+3i)/(1-2i)`

Explanation

Let `z=frac{1+3i}{1-2i}`

`z=frac{1+2i}{1-2i} xx frac{1+3i}{1+3i}`

`=frac{(1-6)+i(3+2)}{1+4}=-1+i`

`:. r=abs(z)=sqrt((-1^2+1^2))=sqrt(2)`

`tan alpha=abs(frac{1}{-1})=1`

`alpha=pi/4`

`arg(z)=pi-alpha=pi-pi/4=3pi/4`