Trigonometry Examples
3i-2
Step 1
Reorder 3i and -2.
-2+3i
Step 2
This is the trigonometric form of a complex number where |z| is the modulus and θ is the angle created on the complex plane.
z=a+bi=|z|(cos(θ)+isin(θ))
Step 3
The modulus of a complex number is the distance from the origin on the complex plane.
|z|=√a2+b2 where z=a+bi
Step 4
Substitute the actual values of a=-2 and b=3.
|z|=√32+(-2)2
Step 5
Step 5.1
Raise 3 to the power of 2.
|z|=√9+(-2)2
Step 5.2
Raise -2 to the power of 2.
|z|=√9+4
Step 5.3
Add 9 and 4.
|z|=√13
|z|=√13
Step 6
The angle of the point on the complex plane is the inverse tangent of the complex portion over the real portion.
θ=arctan(3-2)
Step 7
Since inverse tangent of 3-2 produces an angle in the second quadrant, the value of the angle is 2.15879893.
θ=2.15879893
Step 8
Substitute the values of θ=2.15879893 and |z|=√13.
√13(cos(2.15879893)+isin(2.15879893))