Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

**BLANK****Guest**

Prove that if w,z are complex numbers such that |w|=|z|=1 and wz!= -1, then (w+z)/(1+wz) is a real number.

**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,322

hi BLANK,

Welcome to the forum.

I think this has been asked before and fairly recently but I haven't managed to find it yet. You have typed

wz!= -1

which seems like a typo. ! would be 'factorial' and that makes no sense in this context. If we drop the ! then wz = -1 and that also makes no sense as it makes the denominator of the expression zero.

Please respond with a clarification.

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,322

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**dogleg****Member**- Registered: Yesterday
- Posts: 1

Hi. I am new to this forum and very rusty in my math. I am trying to relearn roots of expressions like : Square root of x-3 = , and fourth root of x-3 for example. Help me get started please.

Offline

**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,322

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

Pages: **1**