## anonymous 5 years ago can someone help me with matrices?

1. anonymous

Hey Rld!

2. anonymous

Like how do I find and inverse of a matrix using the product of elementary matrices

3. anonymous

Hey mhp :D

4. anonymous

I need to find the inverse of a matrix using elementary matrices What doe sthat mean?

5. 2bornot2b

The inverse of a given matrix is a matrix, which when multiplied with the given matrix gives identity.

6. amistre64

there is something called a cofactor matrix, that is tranposed and then divided out by the determinate of the original

7. anonymous

no I need to use the product of the elemntary matrices idk

8. amistre64

youll have to define what that is

9. anonymous

LOL It tells me to find the inverse of a amtrix using elementary matrices

10. anonymous

What do u think that means?

11. anonymous

if i copy from a book if AB=BA = I

12. anonymous

theres more to it though

13. amistre64

\begin{pmatrix}a&b&c\\e&f&g\\h&j&k\end{pmatrix} \begin{pmatrix}+|\begin{array}c f&g\\j&k\end{array}|\end{pmatrix} cant tell if that formats

14. anonymous

can u guys plz help me with my question?

15. amistre64

$\begin{pmatrix}+|\begin{array}c f&g\\j&k\end{array}|& -|\begin{array}c e&g\\h&k\end{array}|& +|\begin{array}c e&f\\h&j\end{array}|\\ -|\begin{array}c b&c\\j&k\end{array}|& +|\begin{array}c a&c\\h&k\end{array}|& -|\begin{array}c a&b\\h&j\end{array}|\\ +|\begin{array}c b&c\\f&g\end{array}|& -|\begin{array}c a&c\\e&g\end{array}|& +|\begin{array}c a&b\\e&f\end{array}|\\ \end{pmatrix}^T\frac{1}{det}=inverse$ those sub matrixes are the determinants values of those things

16. amistre64

dunno if its what its calling for tho :/

17. Zarkon

those are not elementary matrices

18. anonymous

noooo they want something simple but obviously they didnt show an example and like i cant figure it out

19. Zarkon

here is an example ... http://stattrek.com/matrix-algebra/how-to-find-inverse.aspx

20. amistre64

bummer, i memorized it for naught lol

21. anonymous

Thanks amistre lol

22. amistre64

isnt that the gauss jordon?

23. anonymous

Ya s/t like that LOL

24. anonymous

Zarkon that is what I needed

25. anonymous

Thanks Guys :DDDD

26. anonymous

ty zarkon

27. anonymous

i didnt have to type the rst of the stuff

28. anonymous

lol didnt forget abt yesterday mth. Do u still need help?

29. anonymous

im just getting it from the book :P

30. anonymous

hmmm correct me if i am wrong on a coordinate plane the sine and cosine waves to find their angle measurement would it just be the same same way as finding them in a regular circle then to find their line measure how to do that if it was just plot right in the middle of a coordinate plane

31. anonymous

|dw:1327259052486:dw| This is how u wld draw it

32. anonymous

this is a sin curve

33. anonymous

now there is another thing of evaluating triangles like the degrees and measurements sohcahtoa

34. anonymous

|dw:1327259201697:dw| have u ever seen this?

35. anonymous

|dw:1327259258899:dw|

36. anonymous

Do u know what I am talking abt?

37. anonymous

umm sohcahtoa i know

38. anonymous

ohhh so u r not referring to that

39. anonymous

sin curve cosine curve i know

40. anonymous

wait

41. anonymous

ok i guess i am XD

42. anonymous

i just have not seen the second to last drawing

43. anonymous

oh it is abt cast

44. anonymous

45. anonymous

In the first quadrant A=ALL is positive In the second quadrant S = Sin only sin is positive while verything else is negative In the third quadrant T= Tan only tan is positive In the fourth quadrant C=only cos is positive

46. anonymous

This is referring to triangles in the coordinate plane. It all depends in which quadrant the triangle is in

47. anonymous

ooo

48. anonymous

I dont think that was clear

49. anonymous

LOL I need to review my trig I learnt it so long ago

50. anonymous

K I gotta go :((((( i am behind in my work

51. anonymous

Too much work and little time I hope my prof will give me an extension. She aleady gave me one last week lOL

52. anonymous

all i know about the coordinate plane is that quadrant 1 = y is +, x is + quad 2 = y is +, x is- quad 3 = y is - , x is - quad 4 = y is - , x is +

53. anonymous

lol

54. anonymous

you very lucky

55. anonymous

bb

56. anonymous

ty

57. anonymous

LOL I didnt help u much

58. anonymous

help is help i appreciate all i get

59. anonymous

I wish i wld be able to help but i am so busy. i tutor and then I took on this subbing job

60. anonymous

I AM SO BUSY I HATE IT. I WISH I HAD TIME FOR MYSELF

61. anonymous

:P

62. anonymous

U became so serious suddenly lol

63. anonymous

lol

64. anonymous

Its like u r a diff person

65. anonymous

i like to make fun of life

66. anonymous

never serious but it gets to the point :)

67. anonymous

lol

68. anonymous

besides where did you see me do such a thing ?

69. anonymous

What be serious ??????? right now lol

70. anonymous

hehe

71. anonymous

no can do sawy

72. anonymous

huh?

73. anonymous

i dont know being serious is something i can do easily i dont know why

74. anonymous

LOL hard to believe gonna get back to work

75. anonymous

go go go

76. anonymous

LOL I dont know how to leave os

77. anonymous

i dont be the one to cause apocalyse

78. anonymous

huh? what doe sthat mean?

79. anonymous

apocalypse is kinda --end of the world

80. anonymous

mth r u someone else?

81. anonymous

im lazy to make another account and have a bad memory of pw

82. anonymous

LOL the comp remembers it for u

83. anonymous

I have a feeling that u r hero

84. anonymous

LOL no response

85. anonymous

i hate flipping pages to find the pw

86. anonymous

then there is email account

87. anonymous

then theres another account

88. anonymous

this account

89. anonymous

and that

90. anonymous

ugg

91. anonymous

It simpler than u think

92. anonymous

U amy be hero lol

93. anonymous

of course its easy but im lazy remember

94. anonymous

R u hero?

95. anonymous

nope

96. anonymous

LOL u r acting like him lol

97. anonymous

how does he act?

98. anonymous

LOL not telling u

99. anonymous

well hes typing now

100. anonymous

so i dont see how i can be him/her

101. anonymous

LOL OK

102. anonymous

cutter10 question

103. anonymous

^^

104. anonymous

lol no

105. anonymous

lol humor is fun

106. anonymous

LOL

107. anonymous

i have leeched an hour of you work time not that i want you to leave but i really want you to get your work done