roots of equations (1 Viewer)

homijoe

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hey guys, just wanted to ask a quick question. if you had to find the sum of the roots of the equation x^3-3x+5=0, how do u got about doing it since in this particular question the powers of x do not fall from cubic to quadratic to linear, rather it falls from cubic to linear. in other words whats 'a' and 'b' and 'c'... for -b\a and c\a etc.
 

clintmyster

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well you just consider the fact that in that eqn, there is still is "0x2" and then you work from there so the sum of roots = -b/a = -0/1 = 0
 

Timothy.Siu

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homijoe said:
hey guys, just wanted to ask a quick question. if you had to find the sum of the roots of the equation x^3-3x+5=0, how do u got about doing it since in this particular question the powers of x do not fall from cubic to quadratic to linear, rather it falls from cubic to linear. in other words whats 'a' and 'b' and 'c'... for -b\a and c\a etc.
if roots are p,r,s

p+r+s=-0/1=0
 

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