The completely factored form of 2d4 + 6d3 − 18d2 − 54d is

2d(d + 3)^2(d - 3)

Step-by-step explanation:

2d^4 + 6d^3 - 18d^2 - 54d

= 2d^3(d + 3) - 18d(d + 3)

= (2d^3 - 18d)(d + 3)

= 2d (d^2 - 9)(d + 3)

= 2d(d + 3)^2(d - 3)

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: