Chapter 5.7(b) factoring by special products.notebook
February 10, 2017
Bellwork:
Homework Questions???
1) Graph the line y + 3 = 2(x ­ 4)
2) Write the equation of the line parallel to the above line that passes though the point (0, 6).
Factor:
3) x2 ­ 8x + 16
4) 4a2 ­ 25b2
Jan 27­3:46 PM
Jan 27­3:49 PM
Sum and Difference of Two Cubes
Sum: a3 + b3 = (a + b)(a2 ­ ab + b2)
Chapter 5.7(b) Factoring by Special Products
Factor the sum or difference of two cubes.
Difference: a3 ­ b3 = (a ­ b)(a2 + ab +b2)
Let's check why this works:
(x + 4)(x2 ­ 4x + 16)
Jan 27­3:49 PM
1) Factor
a3 + b3 = (a + b)(a2 ­ ab + b2)
a3 ­ b3 = (a ­ b)(a2 + ab + b2)
Jan 27­3:50 PM
a3 + b3 = (a + b)(a2 ­ ab + b2)
a3 ­ b3 = (a ­ b)(a2 + ab + b2)
2) Factor
a. b3 ­ 64
a. x3 + 27
Identify a and b
Identify a and b
Substitute a and b into the formula
Substitute a and b into the formula
b. y3 ­ 125 b. m3 + 8
Jan 27­4:02 PM
Jan 27­4:08 PM
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Chapter 5.7(b) factoring by special products.notebook
3) Factor
a3 + b3 = (a + b)(a2 ­ ab + b2)
a3 ­ b3 = (a ­ b)(a2 + ab + b2)
a. x3 + 64y3
February 10, 2017
a3 + b3 = (a + b)(a2 ­ ab + b2)
a3 ­ b3 = (a ­ b)(a2 + ab + b2)
4) Factor
a. 27a2 + b3a2
Identify a and b
GCF?
Substitute a and b into the formula
Identify a and b
Substitute a and b into the formula
b. 250n3x2 ­ 432x2 b. 27 ­ y3
Jan 27­4:08 PM
Jan 27­4:09 PM
What can you do to help remember the signs when factoring sums of differences of cubes?
a3 + b3 = (a + b)(a2 ­ ab + b2)
Homework: P. 311 #17­28(all)
a3 ­ b3 = (a ­ b)(a2 + ab + b2)
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Jan 27­4:12 PM
Jan 25­1:15 PM
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