Question 8(a)
[Maximum number: 2]
Given that z=1+y i and that y is a real number, express in the form a+b i, where a and b are functions of y.
CAIE A-Level Mathematics 3.9.2 Complex Arithmetic
Practise adding, multiplying and dividing Cartesian complex numbers, rationalising quotients and solving equations by substituting z = x + iy and equating components.
How this is tested
- expand products using i² = −1 and collect the real and imaginary components
- multiply a quotient by the conjugate of its denominator and simplify into x + iy
- substitute z = x + iy, equate components and combine with modulus or reality conditions