## anonymous one year ago square root of -5 multiplied by square root of 5

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1. j2lie

-5 and 5 does not have a perfect square root.

2. anonymous

$\sqrt{-5} \times \sqrt{5}$

3. anonymous

So what does that mean?

4. j2lie

The square root is between 2 and 3.

5. anonymous

I dont get it

6. j2lie

the square root is either 2.5 or below.

7. kropot72

$\large \sqrt{-1}=i$ The square root of negative one is the imaginary number i. Factorising the square root of negative 5 we get: $\large \sqrt{-5}\times \sqrt{5}=(\sqrt{5}\times \sqrt{5})i$

8. kropot72

The get the answer, which is an imaginary number, just simplify the bracketed terms.

9. anonymous

How do I simplify bracketed terms

10. kropot72

Multiply the square root of 5 by the square root of 5.

11. Teddyiswatshecallsme

I think its. $\sqrt{-5} {\times} \sqrt{5} = \sqrt[4]{-25}$

12. j2lie

That makes more sense. @Teddyiswatshecallsme

13. anonymous

Im confused now.

14. kropot72

$\large (\sqrt{5}\times \sqrt{5})i=5i$

15. anonymous

Its -5

16. kropot72

The correct result must be an imaginary number.

17. anonymous

So is @Teddyiswatshecallsme right or @kropot72

18. kropot72

Has anybody given Teddy a medal?

19. anonymous

No

20. kropot72

21. zzr0ck3r

@kropot72 is absolutely correct. Trust the person that shows there work, because if they are wrong you can find it in their work $$\sqrt{5}\sqrt{-5}=\sqrt{5}\sqrt{-1*5}=\sqrt{5}\sqrt{5}\sqrt{-1}=5\sqrt{-1}=5i$$

22. zzr0ck3r

their*

23. anonymous

|dw:1441246950614:dw|

24. kropot72

@zzr0ck3r Thank you for confirmation :)