Determine an equation for the pictured graph. Write your answer in factored form and assume the leading coefficient is either 1 or -1, you should be able to determine which is the case by looking at the graph.

Determine an equation for the pictured graph Write your answer in factored form and assume the leading coefficient is either 1 or 1 you should be able to determ class=

Respuesta :

Ok so here we need to find a suitable equation for this graph. Since we are being asked for a factored form the equation is a polynomial one:

[tex]y=a\cdot(x-r_1)^A\cdot(x-r_2)^B\cdot(x-r_3)^C\ldots[/tex]

Where the r terms represent the roots of the equation which are the points where there are x-intercepts. So first let's identify these points. The graph has three x-intercepts: x=-2, x=0 and x=1 so we have:

[tex]\begin{gathered} y=a\cdot(x-(-2))^A\cdot(x-0_{})^B\cdot(x-1_{})^C \\ y=a\cdot(x+2)^A\cdot x^B\cdot(x-1_{})^C \end{gathered}[/tex]

To find the exponents A, B and C we need to look at the sign of the graph near each x-intercept. If in a given x-intercept the graph changes its sign then the exponent is an odd number. If it doesn't then its an even number.

In the case of x-intercept at x = -2 you can see that the graph changes from negative values to positive values so the exponent A has to be an odd number, let's choose 1. On x=0 the graph sign changes again, it's positive at the left and negative at the right so B is also an odd number and we'll choose number 1 again. Finally on x=1 the graph is negative on both sides of the intercept so C is an even number, let's say 2. All in all we have A=B=1 and C=2. Then:

[tex]\begin{gathered} y=a\cdot(x+2)^1\cdot x^1\cdot(x-1_{})^2 \\ y=a\cdot(x+2)^{}\cdot x^{}\cdot(x-1_{})^2 \end{gathered}[/tex]

So we just need to find a. You can notice that for very large values of x (for x>1) the value of the function must be negative. So let's take a random value ok x that is bigger than 1 let's say 10:

[tex]\begin{gathered} y=a\cdot(10+2)^{}\cdot10^{}\cdot(10-1_{})^2 \\ y=a9720 \end{gathered}[/tex]

So we have y=9720*a and according to what I stated before this value must be negative. 9720 is a positive number so "a" has to be negative and since the two possible options for a are 1 or -1 then we have that a=-1. Then:

[tex]y=(-1)\cdot(x+2)^{}\cdot x^{}\cdot(x-1_{})^2[/tex]

RELAXING NOICE
Relax