Complex Numbers MATHS - Complex Numbers

• A
  $\cos\frac{\pi}{2}+\text{i}\sin\frac{\pi}{2}$
• B
  $\cos\pi+\text{i}\sin\pi$
• C
  $\cos\pi-\text{i}\sin\pi$
• ✓
  $\cos\frac{\pi}{2}-\text{i}\sin\frac{\pi}{2}$

Answer: D.

• A
  $60^\circ$
• B
  $120^\circ$
• C
  $210^\circ$
• ✓
  $240^\circ$

Answer: D.

• A
  $\cot\frac{\theta}{2}$
• B
  $\cot\theta$
• ✓
  $\text{i}\cot\frac{\theta}{2}$
• D
  $\text{i}\tan\frac{\theta}{2}$

Answer: C.

• A
  Circle $x^2+ y^2 = 1$
• ✓
  The x-axis
• C
  The y-axis
• D
  The line x + y = 1

Answer: B.

• A
  $|\text{z}|^2>|\text{z}|^2$
• ✓
  $|\text{z}|^2=|\text{z}|^2$
• C
  $|\text{z}|^2<|\text{z}|^2$
• D
  $|\text{z}|^2\geq|\text{z}|^2$

Answer: B.