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**

**notamathperson****Member**- Registered: 2005-09-13
- Posts: 5

I understand my homework pretty well this time, but I do have a couple questions:

Simplify (√-4) x (√-8)

I ended up getting 2√8, but I'm not sure if this is correct

Also, can this number be simplified any more: (2+2i√14) / 6?

Specifically, can the square root be simplified or could it look something like this: (1+i√14) / 3?

Offline

**kylekatarn****Member**- Registered: 2005-07-24
- Posts: 445

√(-4).√(-8) = √(4)i.√(8).i = 2√(8).i² = -2√(8) = -2√(2³) = -2√(2.2²) = -4√(2)

```
2 + 2i√14 2 2i√14 1 √14 1+i√14
--------- = - + ----- = - + ---i or, if you want ------
6 6 6 3 3 3
```

Offline

**notamathperson****Member**- Registered: 2005-09-13
- Posts: 5

Thanks Kyle, I appreciate it.

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,558

Ohhh, multiplying negative square roots is a weird one.

Perhaps it should be: ±4√(2)

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

Offline

Pages: **1**