1. Please open your laptops and pull up Quiz 10.2. Only the provided online calculator may be used on this quiz. You may use your yellow formula sheet for the quiz. (If you don’t have yours with you, ask us for a pink sheet.)

2. Please CLOSE YOUR LAPTOPS, and turn off and put away your cell phones, and get out your note- taking materials.

3. Last two weeks of class: Today: (Monday, April 27) Lecture on Section 10.3 (Simplifying radicals) Tuesday & Wednesday this week: Lectures on Section 11.2 & 11.5 (Quadratic formula 1 & 2) Quizzes on HW 10.3 & 11.2 Thursday this week: Lecture: Review for Test 4 (Practice Test 4 due on Monday) Quiz on HW 11.5 NEXT WEEK: Monday, May 4: Test 4 on all sections since Test 3 (60 points, mostly on new material, plus a few questions from Test 3.) Tuesday –Thursday next week: Review lectures on Units 1-3 (Tests 1-3) Review HW on each unit, worth double points (8 pts each)

4. Make sure you know the day and time of the final exam for this section of Math 110: All Math 110 finals will be given in your regular classroom. (Next slide shows final exam schedules for all sections.)

6. Section 10.3 Simplifying Radical Expressions

7. Examples: Recall these square root problems from Section 10.1: (7 2 ) ½ =

8. What we did in the previous examples was essentially to divide the exponent of each base by 2, which is index of the radical for square roots. Think of this as dividing the exponent 7 by the index 2 Two goes into seven 3 times with a remainder of 1

9. Example Simplify First, break down 12 into its prime factors: 12 = 4∙3 = 2∙2∙3 = 2 2 ∙3 1 This gives Now divide the exponents by 2 (square root, so the index is 2). Answer:

10. Problem from today’s homework: Start by breaking down 396: 396 (use your calculator, and start by dividing by 2) 2 198 2 99 9 11 3 3 So 396 = 2 2 3 2 11 1 2 2 3 2 11 1 x 6 y 15 Final Answer: -

11. If we have a radical with an index of 3 or higher, we can use the same process to simplify the radical. Divide the exponent 7 by the index 3 Three goes into seven 2 times with a remainder of 1

12. Example Simplify Answer:

13. Problem from today’s homework:

14. If and are real numbers, then Why is this condition important? No, because square roots of negative numbers are not real numbers. Product and Quotient Rules for Radicals: Product Rule: Quotient Rule: Because division by zero gives an undefined quotient.

15. Simplify the following radical expressions. Example (Assume x and y are ≥ 0) (Assume a > 0 and b ≠ 0)

16. Problem from today’s homework:

17. 5

18. Example Use the quotient rule to divide, then simplify if possible: Answer:

19. In previous chapters, we’ve discussed the concept of “like” terms. These are terms with the same variables raised to the same powers. They can be combined through addition and subtraction. Example: (x 2 + 5x – 1) + (6x 2 - 3x + 4) = 7x 2 + 2x + 3 Similarly, we can work with the concept of “like” radicals to combine radicals with the same radicand.

20. Like radicals are radicals with the same index and the same radicand. Like radicals can also be combined with addition or subtraction by using the distributive property.

21. Can not simplify (different indices) Can not simplify (different radicands) Example

22. Always simplify radicals FIRST to determine whether there are like radicals to be combined.

23. Simplify the following radical expression. Example

24. REMINDER: The assignment on today’s material (HW 10.3) is due at the start of the next class session. Please open your laptops and work on the homework assignment until the end of the class period. Lab hours in 203: Mondays through Thursdays 8:00 a.m. to 6:30 p.m. Please remember to sign in on the Math 110 clipboard by the front door of the lab