1. 5.3 Multiplying Polynomials
Brett Solberg – AHS – ’11-’12

2. Warm-up October 26 2011 #1 P(x) = 2x2y3 + 8z5 Q(X) = 5z8 – 4x2y3
Find P(x) + Q(x)
Find Q(x) – P(x)
#2 Distribute the following
x(2x + 4)
(x + 4)(2x – 1)
Do you have any HW questions?

3. Today’s Agenda Multiplying Polynomials Reminder: End of Quarter
Distribution
Binomials
FOIL
Squaring Binomials
Multiplying Sums and Differences
Reminder: End of Quarter

4. Activity
I need 7 volunteers.

5. Distribution Milk Duds(Bob + Sue) = M.D Bob + M.D Sue
a(b + c) = ab + ac
2(x + 3) = 2x + 6
x(3x – 4) = 3x2 – 4x

6. FOIL The order you multiply terms F - First O - Outside I - Inside
L - Last
(Reeses + Rolo)(Megan + Jack)
Reeses Megan + Reeses Jack + Rolo Megan + Rolo Jack
(a + b)(c + d) = ac + ad + bc + bd
(x + 3)(2x + 7) = 2x2 + 7x + 6x + 21

7. (a + b)(c + d + e) = ac + ad + ae + bc + bd + be (x + 2)(x2 -4x + 3) = x3 - 4x2 + 3x + 2x2 – 8x + 6 x3 – 2x2 - 5x + 6 Do the first 3 examples on your worksheet.

8. Squaring Sums (a + b)2 (a+ b)(a + b) a2 + 2ab + b2 (2x + 7y)2
a = 2x b = 7y
(2x)2 + 2*2x*7y + (7y)2
4x2 + 28XY + 49y2
Do example 5 on the worksheet

9. a
a a2 b
ab b
(a + b)2
a2 + 2ab + b2
b ab a
b2 b b

10. Squaring Sum Activity Fold graph paper in half.
In the top left corner make a square less that 10 x 10 units.
From the bottom left corner of the square make another square less than 10 x 10 units.
Make a big square containing both these squares and label all the sides.

11. Squaring Differences (a - b)2 (a - b)(a - b) a2 - 2ab + b2 (4x2 - 16)2
a = 4x2 b = 16
(4x2)2 – 2*4x2*
16x4 – 128x
Do example 4 on the worksheet.

12. a - b
a - b
a2 – b2 = (a – b)(a + b)

13. Multiplying Sum and Difference
(a + b)(a – b) = a2 – b2
(2x + 4)(2x – 4)
4x2 - 8x + 8x – 16
4x2 – 16
(3xy2 + 8)(3xy2 – 8)
(3xy2)2 – 82
9x2y4 – 64
Do example 6

14. Combination (x + 3)(x – 3)(2x + 1)
Multiplication of Sum and Difference
(x2 – 9)(2x + 1)
FOIL
2x3 + x2 -18x – 9
Do example 7 and 8.

15. Class Assignment
5.3 pg. 217 # 2 – 36 even