Enter a problem...
Linear Algebra Examples
Step 1
Step 1.1
Factor out of .
Step 1.2
Cancel the common factors.
Step 1.2.1
Factor out of .
Step 1.2.2
Cancel the common factor.
Step 1.2.3
Rewrite the expression.
Step 2
Step 2.1
Factor out of .
Step 2.2
Cancel the common factors.
Step 2.2.1
Factor out of .
Step 2.2.2
Cancel the common factor.
Step 2.2.3
Rewrite the expression.
Step 3
Step 3.1
Choose the row or column with the most elements. If there are no elements choose any row or column. Multiply every element in row by its cofactor and add.
Step 3.1.1
Consider the corresponding sign chart.
Step 3.1.2
The cofactor is the minor with the sign changed if the indices match a position on the sign chart.
Step 3.1.3
The minor for is the determinant with row and column deleted.
Step 3.1.4
Multiply element by its cofactor.
Step 3.1.5
The minor for is the determinant with row and column deleted.
Step 3.1.6
Multiply element by its cofactor.
Step 3.1.7
The minor for is the determinant with row and column deleted.
Step 3.1.8
Multiply element by its cofactor.
Step 3.1.9
Add the terms together.
Step 3.2
Evaluate .
Step 3.2.1
The determinant of a matrix can be found using the formula .
Step 3.2.2
Simplify the determinant.
Step 3.2.2.1
Simplify each term.
Step 3.2.2.1.1
Multiply .
Step 3.2.2.1.1.1
Multiply by .
Step 3.2.2.1.1.2
Multiply by .
Step 3.2.2.1.1.3
Multiply by .
Step 3.2.2.1.2
Multiply .
Step 3.2.2.1.2.1
Multiply by .
Step 3.2.2.1.2.2
Multiply by .
Step 3.2.2.1.2.3
Multiply by .
Step 3.2.2.2
To write as a fraction with a common denominator, multiply by .
Step 3.2.2.3
Write each expression with a common denominator of , by multiplying each by an appropriate factor of .
Step 3.2.2.3.1
Multiply by .
Step 3.2.2.3.2
Multiply by .
Step 3.2.2.4
Combine the numerators over the common denominator.
Step 3.2.2.5
Simplify the numerator.
Step 3.2.2.5.1
Multiply by .
Step 3.2.2.5.2
Subtract from .
Step 3.2.2.6
Move the negative in front of the fraction.
Step 3.3
Evaluate .
Step 3.3.1
The determinant of a matrix can be found using the formula .
Step 3.3.2
Simplify the determinant.
Step 3.3.2.1
Simplify each term.
Step 3.3.2.1.1
Cancel the common factor of .
Step 3.3.2.1.1.1
Factor out of .
Step 3.3.2.1.1.2
Factor out of .
Step 3.3.2.1.1.3
Cancel the common factor.
Step 3.3.2.1.1.4
Rewrite the expression.
Step 3.3.2.1.2
Multiply by .
Step 3.3.2.1.3
Multiply by .
Step 3.3.2.1.4
Multiply by .
Step 3.3.2.1.5
Multiply .
Step 3.3.2.1.5.1
Multiply by .
Step 3.3.2.1.5.2
Multiply by .
Step 3.3.2.1.5.3
Multiply by .
Step 3.3.2.2
To write as a fraction with a common denominator, multiply by .
Step 3.3.2.3
Write each expression with a common denominator of , by multiplying each by an appropriate factor of .
Step 3.3.2.3.1
Multiply by .
Step 3.3.2.3.2
Multiply by .
Step 3.3.2.4
Combine the numerators over the common denominator.
Step 3.3.2.5
Simplify the numerator.
Step 3.3.2.5.1
Multiply by .
Step 3.3.2.5.2
Subtract from .
Step 3.3.2.6
Move the negative in front of the fraction.
Step 3.4
Evaluate .
Step 3.4.1
The determinant of a matrix can be found using the formula .
Step 3.4.2
Simplify the determinant.
Step 3.4.2.1
Simplify each term.
Step 3.4.2.1.1
Multiply .
Step 3.4.2.1.1.1
Multiply by .
Step 3.4.2.1.1.2
Multiply by .
Step 3.4.2.1.1.3
Multiply by .
Step 3.4.2.1.2
Cancel the common factor of .
Step 3.4.2.1.2.1
Move the leading negative in into the numerator.
Step 3.4.2.1.2.2
Factor out of .
Step 3.4.2.1.2.3
Factor out of .
Step 3.4.2.1.2.4
Cancel the common factor.
Step 3.4.2.1.2.5
Rewrite the expression.
Step 3.4.2.1.3
Multiply by .
Step 3.4.2.1.4
Multiply by .
Step 3.4.2.1.5
Multiply by .
Step 3.4.2.1.6
Move the negative in front of the fraction.
Step 3.4.2.2
To write as a fraction with a common denominator, multiply by .
Step 3.4.2.3
Write each expression with a common denominator of , by multiplying each by an appropriate factor of .
Step 3.4.2.3.1
Multiply by .
Step 3.4.2.3.2
Multiply by .
Step 3.4.2.4
Combine the numerators over the common denominator.
Step 3.4.2.5
Simplify the numerator.
Step 3.4.2.5.1
Multiply by .
Step 3.4.2.5.2
Subtract from .
Step 3.5
Simplify the determinant.
Step 3.5.1
Simplify each term.
Step 3.5.1.1
Multiply .
Step 3.5.1.1.1
Multiply by .
Step 3.5.1.1.2
Multiply by .
Step 3.5.1.1.3
Multiply by .
Step 3.5.1.2
Multiply .
Step 3.5.1.2.1
Multiply by .
Step 3.5.1.2.2
Multiply by .
Step 3.5.1.2.3
Multiply by .
Step 3.5.1.2.4
Multiply by .
Step 3.5.1.2.5
Multiply by .
Step 3.5.1.3
Multiply .
Step 3.5.1.3.1
Multiply by .
Step 3.5.1.3.2
Multiply by .
Step 3.5.1.3.3
Multiply by .
Step 3.5.2
Combine the numerators over the common denominator.
Step 3.5.3
Add and .
Step 3.5.4
Add and .
Step 4
Since the determinant is non-zero, the inverse exists.
Step 5
Set up a matrix where the left half is the original matrix and the right half is its identity matrix.
Step 6
Step 6.1
Multiply each element of by to make the entry at a .
Step 6.1.1
Multiply each element of by to make the entry at a .
Step 6.1.2
Simplify .
Step 6.2
Perform the row operation to make the entry at a .
Step 6.2.1
Perform the row operation to make the entry at a .
Step 6.2.2
Simplify .
Step 6.3
Perform the row operation to make the entry at a .
Step 6.3.1
Perform the row operation to make the entry at a .
Step 6.3.2
Simplify .
Step 6.4
Multiply each element of by to make the entry at a .
Step 6.4.1
Multiply each element of by to make the entry at a .
Step 6.4.2
Simplify .
Step 6.5
Multiply each element of by to make the entry at a .
Step 6.5.1
Multiply each element of by to make the entry at a .
Step 6.5.2
Simplify .
Step 6.6
Perform the row operation to make the entry at a .
Step 6.6.1
Perform the row operation to make the entry at a .
Step 6.6.2
Simplify .
Step 6.7
Perform the row operation to make the entry at a .
Step 6.7.1
Perform the row operation to make the entry at a .
Step 6.7.2
Simplify .
Step 7
The right half of the reduced row echelon form is the inverse.