Question 401301
Factor completely.
1. 6x^6 + 8x^4 – 15x^3 – 20x


2. 9x^2 – 27x + 20

3. 2x^2 – 128

1. 6x^6 + 8x^4 – 15x^3 – 20x
  =2x^4(3x^2+4)-5x(3X^2+4)
  =(3x^2+4)(2x^4-5x)
  =(3x^2+4)(2x^3-5)(x)

2. 9x^2 – 27x + 20 (set to zero and solve quadratic equation)
  =(3x=5)(3x-4)

3. 2x^2 – 128
  =x^2=128/2
  =x^2-64 (difference of squares)
  =(x+8)(x-8)