Complex numbers in MATLAB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a complex number with real part 3 and imaginary part 4.

MATLAB

z = 3 + [1] * 4;

Drag options to blanks, or click blank then click option'

Aj

Bi

Ck

Dm

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable other than i or j for the imaginary unit.

Forgetting to multiply the imaginary unit by the imaginary part.

In MATLAB, the imaginary unit is commonly represented by j or i. Here, j is used.

2fill in blank

medium

Complete the code to calculate the magnitude of the complex number z.

MATLAB

magnitude = [1](z);

Drag options to blanks, or click blank then click option'

Aabs

Bmag

Cmod

Dlength

Attempts:

3 left

💡 Hint

Common Mistakes

Using length which returns the size of an array, not magnitude.

Using mod which is for modulus operation on integers.

The abs function in MATLAB returns the magnitude (or absolute value) of a complex number.

3fill in blank

hard

Fix the error in the code to get the phase angle of the complex number z.

MATLAB

angle_value = [1](z);

Drag options to blanks, or click blank then click option'

Aphase

Batan

Carg

Dangle

Attempts:

3 left

💡 Hint

Common Mistakes

Using phase which is not a MATLAB function.

Using arg which is not recognized in MATLAB.

The MATLAB function angle returns the phase angle (in radians) of a complex number.

4fill in blank

hard

Fill both blanks to create a complex number from magnitude 5 and angle pi/4.

MATLAB

z = [1] * (cos([2]) + 1i * sin(pi/4));

Drag options to blanks, or click blank then click option'

A5

Bpi/4

Cpi/2

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong angle value inside cosine and sine.

Confusing magnitude with angle.

The complex number in polar form is magnitude times (cos(angle) + i*sin(angle)). Here, magnitude is 5 and angle is pi/4.

5fill in blank

hard

Fill all three blanks to create a vector of complex numbers with real parts 1 to 3 and imaginary parts 4 to 6.

MATLAB

z = [1] + [2] * [3];

Drag options to blanks, or click blank then click option'

A1:3

B1i

C4:6

D1j

Attempts:

3 left

💡 Hint

Common Mistakes

Using 1j instead of 1i (both work but only one is correct here).

Mixing up the ranges for real and imaginary parts.

The vector z is created by adding the real parts 1:3 to the imaginary parts 4:6 multiplied by the imaginary unit 1i.