3. represents the sets with a venn diagram: u = {1,2,3,4,5,6,7,8,9, 10, 11, 12} a = {1,2,3,4,6, 12} b = {1,2,4,8}

See explanation and picture attached

Step-by-step explanation:

A set can be described by listing all of its elements.  

For example, A = { 2, 4, 6, 8}, which we read as  

“A is the set whose elements are 2, 4, 6 and 8”.  

The four elements of the set are separated by commas, and the list is enclosed between curly brackets.  

A set can also be described by writing a description of its elements between curly brackets.  

Thus the set A above can also be written as  

A = { even natural numbers less than 9 }, which we read as  

“A is the set of even natural numbers less than 9”.  

A set can also be described graphically by using Venn diagrams, which are simply circle shaped drawings showing the elements inside.

In our case U={1,2,3,4,5,6,7,8,9,10,11,12} A={1,2,3,4,6,12} B={1,2,4,8}

See picture attached for the answer.

$9.41

step-by-step explanation:

x² + 11x + 18 < 0  

[-11 ± sqrt(121 - 72)]/2 = (-11 ± 7)/2  

solution: (-9, -2)

step-by-step explanation: