`5 + 2i` Write the trigonometric form of the number.

`5+2i`

Take note that the trigonometric form of a complex number z=x+yi is

`z=r(cos theta + isin theta)`

where 

`r=sqrt (x^2+y^2)`

and

`theta = tan^(-1) y/x`

Applying these formula,  the values of r and theta of `z=5+2i` are:

`r=sqrt(5^2+2^2)=sqrt(25+4)=sqrt29`

`theta = tan^(-1) 2/5 = 21.8^o`

Plugging them to the trigonometric form, it result to:

`z=sqrt29 (cos 21.8^o + isin21.8^o)`

Thus, the trigonometric form of  `5+2i`  is  `sqrt29(cos21.8^o + isin21.8^o)` .