f(x)=x^3-x^2-36x+36/x^3-17x^2+90x-144, f(x) has one hole point at(__,__)
someone really wants you to learn to factor
well i know how to factor that out but i dont know what the hole point is
the hole appears when the top and bottom have a like factor
determine the common roots and youll see your "x" value; simplify and input the x again to get the y
never mind this one doesnt seem like it factors nicely
it will factor, find 1 rational factor and then use synthetic division to get the rest
for example: \[\frac{(x-1)(x+2)}{(x+2)(x-3)}\] x+2 is common and has a root at -2 \[\frac{(-2-1)\cancel{(x+2)}}{\cancel{(x+2)}(-2-3)}=\frac{3}{5} \]
even easier way is to use grouping method on first fraction
numeratpr(
i tried factoring but cant do i have to use the quadratic formula or am i just making it harder than what it is
x^3-x^2-36x+36 x^2(x-1)-36(x-1) (x-1)(x^2-36) (x-1)(x-6)(x+6) <===numerator
Quadratic formula is for quadratics, not cubics
lol "someone really wants you to learn to factor" And this is why high school math before AP sucked.
For the denominator, i'm going to find a zero on a calculator and use that to try synthetic division
ok thanks cause i get for the denominator x^2(x-17)18(5x-8) and that cant be right
x^3-17x^2+90x-144, 3| 1 -17 90 -144 3 -42 144 --------------------------- 1 -14 48 | 0 x^2-14x+48=0 (x-6)(x-8)=0 denominator is (x-3)(x-6)(x-8) So in factored form numerator/denominator: \[\frac{(x-1)(x-6)(x+6)}{(x-3)(x-6)(x-8)}=\frac{(x-1)(x+6)}{(x-3)(x-8)}\]
ok thanks for doing that but how do i find the hole
to quote amistre64: "the hole appears when the top and bottom have a like factor" There is one set of like factors in the numerator and denominator: x - 6 So, there would be a hole at x - 6 = 0, or x = 6
i've actually got 2 holes
one at x=3, x=8
actually, x=3,x=8 are vertical asymptotes, not holes
x=6 would be the hole
so its 6,0 and you got the six becasue thats what was common in both of them and you canceled it
f(x) is undefined at x=3,6,8. But because (x-6) is also a factor in the numerator, it is only a hole in the graph, not a vertical asymptote
ok im just trying to figure out how to write it cause it gives me 2 spaces to enter a number and the first space is 6 but i cant fiugure out what goes in the next space
They want a y-value then?
\[\frac{(x-1)(x+6)}{(x-3)(x-8)}\], plug 6 into this expression i posted above
You get the point (6,-10)
ok got it thanks so much
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