HP50g or other: U. of Houston calc exams
08-09-2015, 10:28 PM (This post was last modified: 08-09-2015 10:51 PM by Hlib.)
Post: #19
 Hlib Member Posts: 211 Joined: Jan 2015
RE: HP50g or other: U. of Houston calc exams
Thanks, CR Haeger and Gilles, you rescued me from a failure at exam :-)
On a statement of the problem we have to find parameter "a" without solving system of the linear equations. You simply solved ordinary system, having replaced "a" with "z":
2x -3y = 6 - 7z
-3x + 5y = 7+ 2z
7x +11y = 4 - 6z
I have the same result. It seems to me, it is not a proved trick. We must have:
rank[[2 -3][-3 5][7 11]]=rank[[2 -3 6-7a][-3 5 7+2a][7 11 4-6a]]<=2,
therefore det[[2 -3 6-7a][-3 5 7+2a][7 11 4-6a]]=0.
Code:
[[2 -3 ′6 - 7a′ ] [-3 5 ′7+ 2a′] [7 11 ′4 - 6a′]] DET 0 = ′a′ ZEROS
a=235/128.
Initially I was going to solve quite so.
What would you do, if:
2x -3y = 6 - 7*SQ(a)
-3x + 5y = 7+ 2a
7x +11y = 4 - 6a ?
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 Messages In This Thread HP50g or other: U. of Houston calc exams - Peter Murphy - 08-05-2015, 04:58 AM RE: HP50g or other: U. of Houston calc exams - Brad Barton - 08-05-2015, 06:40 PM RE: HP50g or other: U. of Houston calc exams - Joe Horn - 08-06-2015, 09:31 AM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-05-2015, 07:06 PM RE: HP50g or other: U. of Houston calc exams - Gilles - 08-05-2015, 07:13 PM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-05-2015, 11:34 PM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-06-2015, 03:33 PM RE: HP50g or other: U. of Houston calc exams - Jlouis - 08-06-2015, 09:31 PM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-08-2015, 06:00 PM RE: HP50g or other: U. of Houston calc exams - DavidM - 08-09-2015, 12:46 AM RE: HP50g or other: U. of Houston calc exams - Hlib - 08-08-2015, 10:19 PM RE: HP50g or other: U. of Houston calc exams - Gilles - 08-08-2015, 10:52 PM RE: HP50g or other: U. of Houston calc exams - Didier Lachieze - 08-09-2015, 01:10 AM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-09-2015, 02:18 AM RE: HP50g or other: U. of Houston calc exams - Hlib - 08-09-2015, 04:49 PM RE: HP50g or other: U. of Houston calc exams - CR Haeger - 08-09-2015, 07:14 PM RE: HP50g or other: U. of Houston calc exams - Gilles - 08-09-2015, 07:46 PM RE: HP50g or other: U. of Houston calc exams - CR Haeger - 08-09-2015, 08:18 PM RE: HP50g or other: U. of Houston calc exams - Hlib - 08-09-2015 10:28 PM RE: HP50g or other: U. of Houston calc exams - CR Haeger - 08-10-2015, 12:07 AM RE: HP50g or other: U. of Houston calc exams - Hlib - 08-10-2015, 02:12 PM RE: HP50g or other: U. of Houston calc exams - CR Haeger - 08-10-2015, 03:42 PM RE: HP50g or other: U. of Houston calc exams - Didier Lachieze - 08-10-2015, 03:50 PM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-12-2015, 04:22 PM RE: HP50g or other: U. of Houston calc exams - Gilles - 08-12-2015, 09:29 PM RE: HP50g or other: U. of Houston calc exams - CR Haeger - 08-12-2015, 11:21 PM RE: HP50g or other: U. of Houston calc exams - Hlib - 08-13-2015, 06:35 PM RE: HP50g or other: U. of Houston calc exams - Thomas Klemm - 08-12-2015, 05:26 PM RE: HP50g or other: U. of Houston calc exams - Thomas Klemm - 08-12-2015, 10:53 PM RE: HP50g or other: U. of Houston calc exams - Peter Murphy - 08-13-2015, 01:10 AM RE: HP50g or other: U. of Houston calc exams - Gerson W. Barbosa - 08-13-2015, 08:26 PM RE: HP50g or other: U. of Houston calc exams - CR Haeger - 08-13-2015, 11:14 PM RE: HP50g or other: U. of Houston calc exams - pier4r - 05-03-2017, 10:19 PM

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