Use synthestic substitution to evaluate the polynomial function for the given value of x.

f(x)=7x^4-3x^3+x^2+5x-9; x=2
A) -83
B) 89
C) 93
D) 159

Question

Use synthestic substitution to evaluate the polynomial function for the given value of x.

f(x)=7x^4-3x^3+x^2+5x-9; x=2
A) -83
B) 89
C) 93
D) 159

amistre64 · Answer

what part are you having issues with?

anonymous · Answer

just the answer, when i did direct i got c, but when i did synthetic i got a @amistre64

amistre64 · Answer

synthetic division has 3 basic parts:  setup, and 2 operations (+ and *)


the setup is to make sure youve got all your exponents accounted for:

      4       3       2    1  0
7x^4-3x^3+x^2+5x-9   they are all there,  i dont bother removing the xs, its just not important, and i put my operation on the bottom line, not next to the top line.



       7x^4  -3x^3  +x^2  +5x  -9
       0                                                 <-- add this row
   -----------------------------
2 )                                                      <-- multiply this row

amistre64 · Answer

7x^4  -3x^3  +x^2  +5x  -9
       0        14        22      46   102                                                 
   -----------------------------
2 )  7         11        23      51    107
                                                ^^^    
                                                 this is the end result

amistre64 · Answer

lol, forgot how to subtract

amistre64 · Answer

102
  -9
----
  93

anonymous · Answer

oh okay I get it now

amistre64 · Answer

the textbooks give a rather non-relateable setup to me.  

why would they put the multiplier all the way at the top where its not retriceociated with anything up there?

why would would we need to strip the variables?  they are useful reminders

amistre64 · Answer

*a.ssociated,  the filter doesnt like that word :)