Factor this equation first. Then find the roots.
-Andy
Need to find the roots of the polynomial equation
x^3-5x^2+7x-35 = 0
I got:
f(1)=-32
f(-1)=-48
f(1/5)=-33
f(-1/5)=-36
f(1/7)=-34
f(-1/7)=-36
f(1/35)=-34
f(-1/35)=-35
I didn't bother rounding decimals but, I got no rational roots.. so If someone could verify this answer? Since my book does not have an answer key...
When factoring x^3-5x^2+7x-35, first try to locate a GCF. In this case, your GCF is 1, so we move on. Try grouping the terms since we have 4 of them. (x^3 - 5x^2) + (7x - 35). We take the GCF of each group: [x^2 (x - 5)] and [7(x - 5)]. Nice, each group has the factor (x-5). Therefore, we can write our original equation as (x-5)(x^2 + 7). Expand (foil) this and check it for yourself!
Any questions, don't hesitate to ask!
-Andy