f(x) = x2 + x - 12 / x + 4

Question

f(x) = x2 + x − 12
              x + 4

 

simplify 

Answer 1

Let's use synthetic division.  f(x) / (x - c).     In dividing by x + 4, to find c, let x + 4 = 0.

     This makes x = -4,   so c = -4. 

     Use the c, and the coefficients, 1, 1, and -12.  We will drop the 1, and multiply by -4 and add.

 

      -4 |  1       1       -12                Using this, we get x² + x - 12     to be x - 3 + 0/(x + 4) or x - 3

          |_____-4____  12___                                          x + 4         

             1     -3        |0