Algebra
Calculus
Trigonometry
Matrix
Question
Factor the expression
(x−3)(x+3)(x2+9)
Evaluate
x4−81
Use a2−b2=(a−b)(a+b) to factor the expression
(x2−9)(x2+9)
Solution
(x−3)(x+3)(x2+9)
Show Solution
Find the roots
x1=−3,x2=3
Evaluate
(x4−81)
To find the roots of the expression,set the expression equal to 0
x4−81=0
Move the constant to the right-hand side and change its sign
x4=0+81
Removing 0 doesn't change the value,so remove it from the expression
x4=81
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±481
Simplify the expression
More Steps
Evaluate
481
Write the number in exponential form with the base of 3
434
Reduce the index of the radical and exponent with 4
3
x=±3
Separate the equation into 2 possible cases
x=3x=−3
Solution
x1=−3,x2=3
Show Solution