solve each equation. state the number and type of roots: PROBLEM: x^(3)+6x+20=0 answer pwease and explanation... ^__^

using factor theorem let x = -2 them f(-2) = )-2(^3 - 12 + 20 = 0 so x = -2 is one root and x + 2 is a factor

ohhhh okiii, thanks :D

BUT,BUT why did u use 2?

just by observation - its not always possible of course

now divide x^(3)+6x+20 by x + 2 gives x^2 - 2x + 10 - solve this to get the other roots

ahhh do i really need to solve them......tooo much work >.<"

x = -(-2) +- sqrt(4 - 4 *1 *10) / 2 - oh right - no. and type of roots there are 3 roots one real - thats the 2 and 2 complex roots as u can see from the above the sqrt is of a negative number

ahhhh i get it now, thank you so much ^^

perhaps theres a simpler way of doing this which i dont know about you r welcome

yea i think there is, cause my alg teacher taught us 2 ways, the long an short, in which i tottly forgot.... ^^" uhhhg meh, im so irresponsible, but thanks dude~

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