Pre-cal 12 Question! Determine the equation in factored form for the polynomial graph. I need the value of 'a' as well. Ex. f(x)= ax^3 +x^2 + x +4 Please wait for the attachment.
Look at the given graph, what are the x intercepts ?
Well, I know that x-int are --> x=-2 multiplicity of 1 x=1 multiplicity of 2 x=3 multiplicity of 1
Excellent! next use factor theorem to write an expression for the polynomial
if \(x=a\) is a zero, then \((x-a)\) is a factor of the polynomial
Yes, until now, this is what I think it is p(x)= (x+2)(x-1)(x-3) we need y-int and value of a
sorry (x-1)^2
use the information about multiplicity too
looks good !
p(x)= a(x+2)(x-1)^2(x-3)
lets see if we can find the value of \(a\)
ok
all we're given is a graph so stare at the graph and see if we could use something. .
y-int?
yeah give it a try
ok wait a moment
it seems y intercept is -3 ?
yeah I think so so, (0,-3)
plug that in and find \(a\)
so, this is what I think it is p(x)=a(x-3)(x-1)^2(x+2) -3= a(-3)(-1)^2(+2) -3=-6a so a= -3/-6= 0.5
looks good !
haha thank you very much for walking me through it. :)
np:)
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