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Use synthetic division to find the function value. Then, check your work using a graphing calculator.

Use synthetic division to find the function value. Then, check your work using a graphing-example-1
User Dontknowhy
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1 Answer

2 votes

we have the function

f(x)=x^4-x^3-7x^2+45x-39

Find out f(-5)

so

Use synthetic division

x^4-x^3-7x^2+45x-39 : (x+5)

x^3-6x^2+23x-70

-x^4-5x^3

-------------------------------

-6x^3-7x^2+45x-39

6x^3+30x^2

----------------------------

23x^2+45x-39

-23x^2-115x

------------------------

-70x-39

70x+350

------------------

311 ----------------> remainder

therefore

f(-5)=311

Verify

using a graphing tool

For x=-5 ------------> f(x)=311 is ok

Use synthetic division to find the function value. Then, check your work using a graphing-example-1
User Eldorado
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