We will show how to perform basic complex numbers computations with the calculator
SHARP EL-520W.
We first need to put the calculator in complex numbers mode (CPLX) by doing the following.
MODE .
.
.
=
Let’s now enter the complex number 3 + 5 i .
3 + 5 b i c =
On the screen, we see 3. To see the imaginary part, we use , to get the 5 i . By pushing
, once more we can go back to 3.
By default, the calculator is in rectangular mode. To confirm this, we should see a little xy on the top left of the calculator. To put the calculator in polar mode, we use rθ . We should now see a little rθ on the top left. To go back to rectangular mode, use xy .
Let’s enter the polar complex number 5 30
◦ .
5 b ∠ c 30 =
On the screen, we see 5. To see the angle, we use , to get the 30. By pushing , once more we can go back to 5.
Example 1.
Convert the complex number 3 + 4 i into polar.
Solution: Enter 3 + 4 i .
3 + 4 b i c =
Let’s convert it to polar.
rθ
We see 5 and by pushing , we get the angle 53 .
13
◦
. The answer is then:
5 53 .
13
◦ .
Example 2.
Convert the complex number 4 60
◦ into rectangular.
Solution: Enter 4 60
◦ .
4 b ∠ c 60 =
Let’s convert it to rectangular.
xy
We see 2 and by pushing , we get 3 .
464 i . The answer is then:
2 + 3 .
464 i.
Example 3.
Evaluate (3 + 4 i )(2 − 5 i ).
Solution:
( 3 + 4 b i c ) × ( 2 5 b i c ) =
We see 26 and by pushing , we get − 7 i . The answer is then:
26 − 7 i.
Example 4.
Evaluate 2 25
◦ + 5 36
◦ .
Solution:
2 b ∠ c 25 + 5 b ∠ c 36 =
We see 6 .
97 and by pushing , we get 32 .
86. The answer is then:
6 .
97 32 .
86
◦