Ch 4.7 Solving Radical Inequalities (Part II)

By: Jasy H, Emily L, Colleen Y

What is an Inequality?

• A statement that one quantity is greater than, or less than another quantity

Can YOU give me an example?

3 > 2

6 > 4

What is the definition for Radical Inequality?

• An equation where the variable occurs under a radical sign

What does that mean?Example :Example :

(3x + 1) < x - 9

* A radical inequality, when graphed, will show the domain

Example 1

Step 1 - Set all radicals in the inequality to zero and then solve for x.

Step 2 - Ignore the inequality and solve as if it were “=”. These values obtained are critical numbers. Use critical numbers to test for the inequality.

Step 3 - Draw a number line with intervals at these critical numbers

Step 4 - Test all the critical numbers in the original inequality to see if they are true to the inequality or not.

•If true, colour in the circle at that point

•* If false, draw a clear dot at that point.

Step 5 - After each critical number is tested, test at least one number that lies between each interval.

If true, check off corresponding interval.

If false, cross out corresponding interval

(DO NOT SHADE)

* Shade out quadrants that have numbers that cannot be solved when substituted into the original inequality.

Step 6 - Shade on the line according to which values are possible for x. Therefore, the inequality reads -1 < x < 8.

Practice!

    

More Practice!