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Maths question

seandineen · 2014-01-28 19:11:17

Does anybody know how to show X^3-8 ________ X-2 As a quadratic equation

28-01-2014 7:11pm

#1

seandineen

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Does anybody know how to show

X^3-8
________
X-2

As a quadratic equation

0

Comments

#2 28-01-2014 7:23pm

Moody_mona

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Two options.

1. Long division, diving the bottom into the top.

2. Factorise the top, it's a difference between two cubes, and cancel.

Factorising will be far quicker once you know how to do it.

0
#3 28-01-2014 7:25pm

Huell

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(x-2)(x^2+2x+4)
______________
(x-2)

and cancel your x-2 above and below line and you get x^2+2x+4

0
#4 28-01-2014 7:32pm

seandineen

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Since ye seem to be maths geniuses on this does anybody know

Given z=-2+i(square root of)5 , express z^2 in rectangular form

0
#5 28-01-2014 7:46pm

Moody_mona

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Write them as two brackets and multiply them algebraically.

Remember sqrt(a) times sqrt(a) = a and that i^2=-1

0
#6 28-01-2014 10:58pm

spurious

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Please stop starting multiple threads on this. If you must, keep them all in the one thread, thanks.

0
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#7 12-02-2015 7:38pm

AHireland2k11

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I have a question for someone good at maths
If z5=-3i, z4=6, z3=5-2i and z2=1-4i

What is

(Z5+z4)-(z3-z2)

0