Question

Find all rational roots of 2x^3 - 7x^2 + 9 = 0.

Answer 1

do you know p/q method ?

Answer 2

@Nnesha - no, sorry.

Answer 3

\[\huge\rm \frac{ p }{ q } =\frac{ constant }{ leading ~cofficient }\]
what is constant and leading coefficient in that equation ??

Answer 4

the constant term is 9 and the leading cofficient is 2.

Answer 5

yes right so p represent constant
q = leading coefficient
so you ahve \[\frac{ 9 }{ 2 } = \frac{ \pm 1, ??? }{ ? }\]
now factor both 9 and 2
write with plus minus sign
for example 1

Answer 6

9 = 1, 2 ,3
2 = 1, 2

Answer 7

yep and 9 too

Answer 8

so you ahve \[\huge\rm \frac{ 9 }{ 2 } = \frac{ \pm 1, \pm 3 , \pm 9??? }{ \pm 1 , \pm 2}\]
2 is not a factor of 9

Answer 9

now write everything in fraction form
for example 1 divide by both 1 nd 2 which is at the denominator \[\huge\rm \frac{ \pm 1 }{ \pm 1 } ,\frac{ \pm 1 }{ \pm 2}\]