The length and breath of a rectangle are (a^2 +ab +b^2) units and (a-b) units. find the area of the rectangle.

a^3 - b^3.

Step-by-step explanation:

Area = length * breadth

= (a - b)(a^2 + ab + b^2)

= a(a^2 + ab + b^2) - b(a^2 + ab + b^2)

= a^3 + a^2b + ab^2 - a^2b - ab^2 - b^3

Note: the 4 middle terms cancel out. So the answer is

a^3 - b^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: