solve the equation in the real number system: x^4-8x^3+16x^2 +8x-17=0
by inspection 1 is a solution
because \[1-8+16+8-17=0\]
so you know this factors as \[(x-1)\times \text{something}\] and you find the something by division
yes...
always check to see if 1 works because it is easy. -1 is easy too. check it
then the answer is x^2-8x+17=0 right??
so you know this factors as \[(x-1)(x^3-4x^2+9x+17)\] by division.
you can use synthetic division to divide by x - 1
sorry i made mistake.
it is \[(x-1)(x^3-7x^2+9x+17)\]
that is the correct answer. now check the second factor and you will see that -1 is a zero
:).. ok...
i am sorry about that and you are right! it is \[(x-1)(x+1)(x^2-8x+17)\] you had it all along!
my mistake i should have read your answer more carefully. you got it! third factor has no real zeros so you are done
you were right 6 lines up. done!
x^2-8x+17=0 right?
yes that is the last factor.
this has no real zeros
and since your instructions were "solve in real number system" you are done. real zeros are 1 and -1
good work!
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