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Hi.

 

I’m stuck on the second part of this polynomial question.

I’ve got the first part:

- A is 2

- B is 1

- C is 2

 

How do I go about solving the second part of this question:

Question

 

Thanks in advance,

bqrs01

 May 14, 2019
 #1
avatar+105277 
+3

The graph "kisses" the x axis at  x = 1   and goes through the x axis at x = -2

 

Therefore....we have that

 

y  =  (x + 2) (x - 1)^2

 

When x = 0, then "c"  =  2

 

So....we have that

 

( x + 2)(x-1)^2  = 2

 

(x + 2) ( x^2 - 2x + 1)  = 2

 

x^3 +2x^2 -2x^2 -4x + x+ 2  = 2

 

x^3 - 3x = 0

 

x( x^2 - 3) = 0       set both factors to 0 and solve for x

 

x = 0        and     x^2 - 3  = 0  ⇒  x^2 = 3 ⇒     x  = ± √3

 

Here's a graph :  https://www.desmos.com/calculator/co5bdggyfq

 

 

cool cool cool

 May 14, 2019
edited by CPhill  May 14, 2019
 #2
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ewwwwwwwwww

 May 14, 2019

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