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## anonymous 4 years ago Help please :D

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1. anonymous

2. anonymous

I need help with part c

3. razor99

srry

4. anonymous

mth3v4 Can you help me plz????

5. anonymous

im not very good with marices but ill "try"

6. anonymous

okkiedokieee

7. anonymous

it will probably take time pulling books

8. anonymous

lol Thanx

9. razor99

did u told me that question

10. anonymous

sorry?

11. anonymous

sorries :(

12. anonymous

dont know this 1

13. razor99

r u ok mth3v4

14. anonymous

I apologize, I didn't know you wanted me to help with this question. I'm taking a look now.

15. anonymous

thanks jemurray. I was busy fighting with someone on os

16. anonymous

So it was fine lol

17. anonymous

Okay, these are just asking for relatively simple verifications. Let me show you how to do the first one.

18. razor99

Jemurray3 and SamIam are typing replies…

19. anonymous

ok i did the first two parts but let me see what u got i really need part c

20. anonymous

Razor are you ok?

21. anonymous

Oh, okay, well if you did the first two I won't bother :) Watch now: $A^{-1}\cdot A = \frac{1}{5}(2I - A) \cdot A = \frac{1}{5}(2I\cdot A - A^2)$ but since $A^2 -2IA + 5I = 0$ as per the assumption, then $2IA - A^2 = 5I$ so plugging that in yields $\frac{1}{5}(5I) = I$ So that is in fact the proper inverse matrix.

22. anonymous

Just processing it give me a sec :D

23. anonymous

OHHHH GOTTTT ITTTTT Thankx jemurray :D

24. anonymous

No problem :)

25. anonymous

R u gonna be around fro much longer?

26. anonymous

For a little while

27. anonymous

ok i may be back :D

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