Answer: √17.
- A √17
- B √18
- C √13
- D 5
Correct answer: A. √17
Explanation: Subtract: z₁-z₂=(2+3i)-(1-i)=(2-1)+(3-(-1))i=1+4i. Compute modulus: |1+4i|=√(1²+4²)=√(1+16)=√17. Answer: |z₁-z₂| = √17
A complex number z = a+ib is plotted as a point (or vector from the origin) on the Argand plane, with the real part along the horizontal axis and the imaginary part along the vertical; its modulus |z| is the vector's length, and its argument θ is the angle from the positive real axis.
Concept context
Complex numbers in a+ib form, modulus, argument, polar form, cube roots of unity, and quadratic equations with complex roots
Read the full Complex Numbers and Quadratic Equations notes →