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9. (a) х = 0 Dit is ook ‘n aanvaarbare antwoord.

(b) 2 х + 6 = 2 х + 6

2 х – 2 х = 6 – 6

0 = 0

  • Hierdie oplossing gee nie ‘n enkele waarde vir х nie.
  • Maar die stelling is waar: Nul is gelyk aan nul.
  • As ons ‘n antwoord kry wat ooglopend waar is, soos 12 = 12 of –3 = –3, ens., dan weet ons dat enige waarde van die veranderlike die vergelyking waar sal maak.
  • Ons gee dus die antwoord: х kan enige waarde aanneem .

(c) 3 – 2 х = –2 – 2 х

–2 х + 2 х = –2 – 3

0 = –5

  • Hierdie antwoord gee nie ‘n waarde vir х nie.
  • Inderwaarheid is die stelling onwaar. Nul is nie gelyk aan negatief vyf nie.
  • As ons ‘n onwaar antwoord kry, soos 5 = –5 of 2 = –9, ens., dan weet ons dat geen waarde van die veranderlike die vergelyking waar sal maak nie.
  • Dus is die antwoord: Daar is geen oplossing nie .

Van nou af moet jy jou oë oophou vir hierdie spesiale gevalle (jy sal hulle nie veel sien nie) en ‘n geskikte antwoord gee

Aktiwiteit 3

Om te bevestig dat oplossings korrek is

[lu 2.4, 2.6]

  • In Wiskunde is dit dikwels moeilik om seker te wees dat jou antwoord korrek is, maar wanneer ons vergelykings oplos, is dit baie maklik: ons kontroleer net ons antwoorde! Dit moet egter baie noukeurig op ‘n spesifieke manier gedoen word.

Dis hoe: Ons kyk weer na vraag 8 hierbo.

(a) 5( х + 1) = 20 gee die oplossing: х = 3

Begin met die oorspronklike vergelyking.

Kontroleer die linkerkant (LK) en regterkant (RK) apart .

Substitueer die oplossing vir х en vereenvoudig:

LK = 5( х + 1) = 5[( 3 ) + 1] = 5(3 + 1) = 5(4) = 20

Soos gewoonlik by substitusie is hakies baie handig.

RK = 20

Omdat die RK en die LK gelyk is, weet ons die oplossing is korrek.

(b) 8 + 4( х – 1) = 0 Veronderstel ons antwoord was х = 2. Toets die antwoord:

LK = 8 + 4( х – 1) = 8 + 4[( 2 ) – 1] = 8 + 4(2 – 1) = 8 + 4(1) = 8 + 4 = 12

RK = 0

Omdat LK ≠ RK weet ons dat 2 nie ‘n oplossing vir die vergelyking is nie.

Natuurlik is die regte antwoord: х = –1. Gaan dit na:

LK = 8 + 4( х – 1) = 8 + 4[( –1 ) – 1] = 8 + 4(–1 – 1) = 8 + 4(–2) = 8 – 8 = 0

LK = RK, en ons het bevestig dat х = –1 die korrekte oplossing is.

(c) х ( х + 3) = х 2 + 6 oplossing: х = 2

LK = х ( х + 3) = ( 2 )(( 2 ) + 3) = 2(2 + 3) = 2(5) = 10

RK = х 2 + 6 = ( 2 ) 2 + 6 = 4 + 6 = 10

LK = RK, dus is х = 2 die korrekte oplossing.

(d) ½ (4 х + 6) = 1 oplossing: х = –1

LK = ½ (4 х + 6) = ½ (4( –1 ) + 6) = ½ (–4 + 6) = ½ (2) = 1

RK = 1

LK = RK, dus is х = –1 die korrekte oplossing.

Gaan nou terug na 5, 6 en 7 en kontroleer jou oplossing op dieselfde manier.

As ons terug gaan na die spesiale gevalle in 9, kan ons hulle ook kontroleer:

(a) 2( х + 1) = х + 2 gee die oplossing: х = 0

LK = 2( х + 1) = 2(( 0 ) + 1) = 2(0 + 1) = 2(1) = 2

RK = х + 2 = ( 0 ) + 2 = 2

LK = RK, dus is х = 0 die korrekte oplossing.

(b) 2( х + 3) = 2 х + 6 Enige getal is ‘n oplossing! Toets bv. 5; of enige ander getal.

LK = 2( х + 3) = 2(( 5 ) + 3) = 2(5 + 3) = 2(8) = 16

RK = 2 х + 6 = 2( 5 ) + 6 = 10 + 6 = 16

LK = RK as х = 5. Inderdaad, LK sal gelyk wees aan RK vir enige waarde.

(c) 3 – 2 х = –2(1 + х ) Daar is geen oplossing nie; probeer 12. Jy kan ander getalle probeer.

LK = 3 – 2 х = 3 – 2( 12 ) = 3 – 24 = – 21

RK = –2(1 + х ) = –2(1 + ( 12 )) = –2(1 + 12) = –2(13) = –26

LK ≠ RK en hulle sal ongelyk wees vir enige getal.

Questions & Answers

I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
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Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
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characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
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How can I make nanorobot?
Lily
how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Wiskunde graad 9. OpenStax CNX. Sep 14, 2009 Download for free at http://cnx.org/content/col11055/1.1
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