Which of the following represents the set of possible rational roots for the polynomial shown below?

2x^3+5X^2-8X-10=0

Question

Which of the following represents the set of possible rational roots for the polynomial shown below?

2x^3+5X^2-8X-10=0

campbell_st · Answer

what choices do you have...?

campbell_st · Answer

you can use the factor theorm to find them... 

substitute the root into the function and show f(a) = 0, where a is a rational root.

anonymous · Answer

sorry i accidentally pressed go. 
A. {+-2/5,1/2,1,2,2/5,1/5,1/10}
B. {+-1,2,4,5,10,20}
C. {+-1/2,1,2,5/2,5,10}
D. {1/2,1,2,5/2,4,5,10,20}

anonymous · Answer

a,b,c all have +- in front of all of the numbers but d doesnt have any.

campbell_st · Answer

ok,,, so the rational root theorem say find the factors of the constant

call them p..... so find the factor of -10   

$$\pm 1, \pm 2, \pm 5, \pm 10$$

then find the factors of the coefficient of the leading term q   in your question its 2

$$\pm 1, \pm 2$$

the the possible rational zeros are p/q

hope it helps

anonymous · Answer

so it would be B, right?