The range of the function fk) k2 2k + 1 is (25, 64). what is the function's domain?

1.  Set f(k) = 25

k2 + 2k + 1 = 25 

k2 + 2k - 24 = 0

(k - 4)(k + 6) = 0

So two limiting values in the domain are -4 and 6

2. Set f(k) = 64

k2 + 2k + 1 = 64

k2 + 2k - 63 = 0

(k - 7)(k + 9) = 0

So the other two limits are -9 and 7

The domain is  [-9, -4] ∪ [6, 7]

- 2 + 10x³ - 21x² + 19x - 4

step-by-step explanation:

each term in the second factor is multiplied by each term in the first factor

x²(- 2x² + 4x - 1) - 3x(- 2x² + 4x - 1) + 4(- 2x² + 4x - 1) ← distribute

= - 2 + 4x³ - x² + 6x³ - 12x² + 3x -8x² + 16x - 4

collect like terms

= - 2 + 10x³ - 21x² + 19x - 4 ← in standard form

a is the right answer