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maths Q from Algebra (1 Viewer)

is2buddaflies

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Show that x= 2/2 - 3 is one of the roots of the equation x^2 + 6x + 1 = 0

/ = squareroot

tks in adv :)
 

chingyloke

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or quadratic formularise it if u want the long way...
 

clintmyster

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LOL such a simple question. I wish this was in our tests ahaha
 

is2buddaflies

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i tried subbing came up with wrong answer. Simple question, lol, maybe for you
 

Timothy.Siu

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is2buddaflies said:
i tried subbing came up with wrong answer. Simple question, lol, maybe for you
i subbed it in and got the correct answer.

subbing it in is the easy way to do this question,
x^2 + 6x + 1 = 0

but u can use quadratic formula i guess or complete the square

x=[-6+-root(36-4)]/2
=-3+-2root2

subbing it in,
LHS=(2root2-3)^2+6(2root2-3)+1=8-12root2+9+12root2-18+1=0
 
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clintmyster

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Show that x= 2/2 - 3 is one of the roots of the equation x^2 + 6x + 1 = 0

by subbing it in

LHS = (2root2 - 3)2 + 6(2root2 - 3) + 1
= 8 - 12root2 + 9 + 12root2 - 18 + 1
= 0
= RHS

How easy was that?
 

tommykins

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It'd be great if you guys actually helped people rather than patronise them in the process.
 

Timothy.Siu

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tommykins said:
It'd be great if you guys actually helped people rather than patronise them in the process.
lol, i was trying to help..seriously, i dunno about the others
 

tommykins

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Timothy.Siu said:
lol, i was trying to help..seriously, i dunno about the others
nah wasn't aiming it at you, more so cuntmyster
 

is2buddaflies

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i wasnt chucking a shit at tommykins, just seconding what he said at clintmyster
LOL should start writing more clearly
 

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