You can put this solution on YOUR website!
You left out the i. It's
z = |z|(cosѲ + i·sinѲ)
That's the trigonometric form of the complex number z = x + iy
The complex imaginary number z = x + yi is represented
by the vector (line segment) from the origin to the point
(x,y). So we draw and arbritrary point (x,y). (x,y) could
be in any quadrant or even on an axis, but we'll draw it in
the first quadrant. We'll label the length of the vector
from the origin to the point (x,y) as |z|.
Now from the point (x,y) we drop a perpendicular to the
x-axis (in green):
That makes a right triangle. The base of that right triangle
is the same as the x-coordinate of the point (x,y), so it is x.
The green side of that right triangle
is the same as the y-coordinate of the point (x,y), so it is y.
The angle that the vector makes with the x-axis is labeled Ѳ.
So from the triangle,
Then we can factor out the and get
That's the trigonometric or "trig" form of the complex
It allows us to bring trig into the algebra of complex
numbers. It will make certain operations simpler.