Create a quadratic polynomial function f(x) and a linear binomial in the form (x − a). Part 1. Show all work using long division to divide your polynomial by the binomial. Part 2. Show all work to evaluate f(a) using the function you created. Part 3. Use complete sentences to explain how the remainder theorem is used to determine whether your linear binomial is a factor of your polynomial function
my functions are (x^3 - 3x^2 - x + 3), and (x - 1).
long division hasnt change since the 3rd grade ....
@dan815 @Danielp @marissalovescats
but it is using polynomials, just a tad harder
its exactly the same hardness as normal :/ -------------------- x - 1 | x^3 - 3x^2 - x + 3 how many times does x go into x^3?
3 times :P
x*x^2 = x^3 .... id say x^2 times
x*x=x^2 then x^2*x=x^3 ohhhhhhhh xD
x^2 -------------------- x - 1 | x^3 - 3x^2 - x + 3 now we mulitply, and subtract, and pull down whats left x^2 -------------------- x - 1 | x^3 - 3x^2 - x + 3 -(x^3 - x^2) ------------ -2x^2 - x + 3 and repeat ... how many times does x go into -2x^2?
2 times?
almost :) x*-2x = -2x^2, lets go with -2x times
oooh i was debating whether -2 or 2...
x^2 - 2x -------------------- x - 1 | x^3 - 3x^2 - x + 3 now we mulitply, and subtract, and pull down whats left x^2 - 2x -------------------- x - 1 | x^3 - 3x^2 -(x^3 - x^2) ------------ -2x^2 - x + 3 -(-2x^2+2x) ------------ -3x + 3 and repeat ... how many times does x go into -3x?
-3 times
yes, this time its just -3 :) -3*x = -3x soo what do we do?
divide by -3?
notice that we are simply playing with first terms such that: x * k = x^3 k = x^3/x = x^2 or again x * k = -2x^2 k = -2x^2/x = -2x
and no we dont divide by -3 ... we use it in the same way weve always used it when doing longhand division .... the same way i demonstrated the two times before
multply, and subtract ....
@amistre64 so do x-1*-3? im confused...
of course ...
mmk little confused spo was checking
so x*-3 is -3x and -1*-3=3
refresh with numbers if its been too long :) 00 ------- 52 | 1245 124/52 = 2.xxx , use 2, 2(52) = 104 002 ------- 52 | 1245 -104 ---- 205 , drop down the 5 and repeat ...
so 20*x-1
20x-20
not sure why youre going with 20 ... -3(x-1) = -3x+3 .... then subtract it from the rest
oh you said drop the 5 so... oh
forgot something so reedit to include that -3 again :) how many times does x go into -3x? -3 times soo x^2 - 2x - 3 -------------------- x - 1 | x^3 - 3x^2 - x + 3 now we mulitply, and subtract, and pull down whats left x^2 - 2x - 3 -------------------- x - 1 | x^3 - 3x^2 -(x^3 - x^2) ------------ -2x^2 - x + 3 -(-2x^2+2x) ------------ -3x + 3 -(-3x + 3) --------- 0, our remainder is simply zero now
so what would we do for part 2?
librarys closing so youre on your own ... or at least im on my own :) good luck
Oh ok thx
Join our real-time social learning platform and learn together with your friends!