Find all x and y intercepts of the graph of the function f(x)= 2x^3+6x^2-2x-6

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Step-by-step explanation:

We notice the first pair of coefficients is the same as the last pair (with the sign changed). This means we can factor by grouping.

  f(x) = (2x^3 +6x^2) -(2x +6)

  f(x) = 2x^2(x +3) -2(x +3)

  f(x) = 2(x^2 -1)(x +3) = 2(x -1)(x +1)(x +3)

The factors are made to be zero when x is 1, -1, or -3.

The x-intercepts are (1, 0), (-1, 0), (-3, 0).

The y-intercept is the constant, -6.

(x3 + 6x2 + 2x - 6) • (x - 1)

step-by-step explanation:

polynomial long division :

3.2     polynomial long division

dividing :   x4+5x3-4x2-8x+6

                              ("dividend")

by         :     x-1     ("divisor")

dividend     x4   +   5x3   -   4x2   -   8x   +   6

- divisor   * x3     x4   -   x3            

remainder         6x3   -   4x2   -   8x   +   6

- divisor   * 6x2         6x3   -   6x2        

remainder             2x2   -   8x   +   6

- divisor   * 2x1             2x2   -   2x    

remainder               -   6x   +   6

- divisor   * -6x0               -   6x   +   6

remainder                     0

quotient :   x3+6x2+2x-6   remainder:   0