Find z̄ × z (where z = a + ib):
Aa² + b² = |z|²
B2a
Ca² - b²
D|z|
Answer & Solution
Correct answer: A. a² + b² = |z|²
We have z × z̄ = (a + ib)(a - ib).
That is z × z̄ = a² - (ib)².
That is z × z̄ = a² + b².
So z × z̄ = |z|².
**So conjugate times itself gives modulus squared.**
Keep practising Unit 3B: Implicit Differentiation and Inverse Functions
Browse all Unit 3B: Implicit Differentiation and Inverse Functions questions for AP Calculus AB, or explore more Mathematics topics.
Related questions
An event is described as having 'EVEN CHANCE'. Its probability is:If you toss a fair coin and the probability of heads is 1/2, what is the probability of NOThe probability of drawing any number from 2 to 10 from a standard deck of 52 cards is:If a bag has 6 cards numbered 1 to 6, and 3 of them are purple, the probability of drawingThe probability of an IMPOSSIBLE event is:Probability measures:Solve 3 ≤ 2x - 1 ≤ 7 (a DOUBLE inequality) for real x.Identify a QUADRATIC inequality (not a linear inequality).