sunmoonlight
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How to do Q16b?
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Compelx numbers (1 Viewer)
- Thread starter sunmoonlight
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How to do Q16b?scaryshark09
∞∆ who let 'em cook dis long ∆∞
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let q be the last root
sum of product of roots 2 at a time = b
(ki)(-ki) + (2)(ki) + (2)(-ki) + (q)(ki) + (q)(-ki) + (2)(q) = b
k^2 +2q = 0
k^2 = -2q
and c = (k^2)(a) {part a}
therefore c = (-2q)(a)
c = 2(-qa)
therefore c is an even number as it is divisible by 2
edit: i am sure there is a better way since this doesn't use the entirety of part a, but it works so who cares
sum of product of roots 2 at a time = b
(ki)(-ki) + (2)(ki) + (2)(-ki) + (q)(ki) + (q)(-ki) + (2)(q) = b
k^2 +2q = 0
k^2 = -2q
and c = (k^2)(a) {part a}
therefore c = (-2q)(a)
c = 2(-qa)
therefore c is an even number as it is divisible by 2
edit: i am sure there is a better way since this doesn't use the entirety of part a, but it works so who cares