Lesson 4

1. Calculate

a)

b)

c)

d)

e)


2. Solve inequalities:

a)

b)


3. Solve using Cramer's rule:

a)

b)

c)

d)

e)

A matrix is in reduced row-echelon form if it satisfies the following: In each row, the left-most
nonzero entry is 1 and the column that contains this 1 has all other entries equal to 0. This 1 is
called a leading 1. The leading 1 in the