1. Daily Check For each equation find the discriminant and the number of solutions.

2. Launched Object h(t) = -16t 2 + 64t + 80 a)How many seconds until the max height is reached? b)What will be the max height? c)How many seconds until the object hits the ground? 2 sec. 144 ft. 5 sec.

3. Math I Day 10 (8-24-09) UNIT QUESTION: What is a quadratic function? Standard: MM2A3, MM2A4 Today’s Question: How do we take the square root of negative numbers? Standard: MM2N1.a, b, c, d

12. You can't take the square root of a negative number, right? When we were young and still in Math I, no numbers that, when multiplied by themselves, gave us a negative answer. Squaring a negative number always gives you a positive. (-1)² = 1. (-2)² = 4 (-3)² = 9

13. So here’s what the math people did: They used the letter “i” to represent the square root of (-1). “i” stands for “imaginary” So, does really exist?

14. Examples of how we use

18. Ex: Solve x 2 + 6x +10 = 0 a = b = c = 1 st 2 nd

19. Complex Numbers A complex number has a real part & an imaginary part. Standard form is: Real part Imaginary part Example: 5+4i

20. The Complex Plane Imaginary Axis Real Axis

21. Graphing in the complex plane

22. Adding and Subtracting (add or subtract the real parts, then add or subtract the imaginary parts) Ex:

23. Graphing in the complex plane

24. Absolute Value of a Complex Number The distance the complex number is from the origin on the complex plane. If you have a complex number the absolute value can be found using:

25. Graphing in the complex plane 2 5

26. Examples 1. 2. Which of these 2 complex numbers is closest to the origin? -2+5i

27. Try These!!! 1. 2. Which of these 2 complex numbers is closest to the origin? 3i3i

28. Practice Coach Workbook Page 21

29. Assignment Page 4 #16-21 Page 8 #6-10 Page 19 #1-10