Question

❤️❤️20 points ♥️♥️♥️

find values of "a" and "b" so that (x+1) and (x-1) are factors of x⁴ + ax³- 3x² + 2x + b.
pls answer in detail step by step​

Answer 1

If we know our two factors, then we know our zeros.  Our zeros are -1 and 1.  What we can do is plug in x=-1 into the polynomial and set it equal to zero.  Then we do the same for x=1.

 

1 - a - 3 - 2 + b = 0     --->   for   x=-1

-a + b = 4                      

 

 

1 + a - 3 + 2 + b = 0   --->    for   x=1

 

a + b = 0

 

 

Now we have a system of equations to work with.

 

-a + b = 4                       eq1

a + b = 0                        eq2

 

 

Add the two equations to eliminate the a terms.

 

2b = 4

 

  b = 2

 

 

Substitute this value of b into any of the equations to solve for a.

 

  a = -2

Answer 2

Answer:

please follow me..............................