140 likes | 536 Views
4.2 Pascal’s Triangle and the Binomial Theorem. Consider the binomial expansions again…. That is, there are ways to get that term. specifically…. Consider the x 2 a term. There are 3 ways to get that term. Pascal’s Triangle using. Value of n 0 1 2 3 4 5. r = 0. r = 1.
E N D
That is, there are ways to get that term. specifically… • Consider the x2a term There are 3 ways to get that term.
Pascal’s Triangle using Value of n 0 1 2 3 4 5 r = 0 r = 1 r = 2 r = 3 r = 4 r = 5
The coefficients of the form are called binomial coefficients. Binomial Theorem
Expand and simplify using the binomial theorem • (x + y)6 • (2x – 1)4
Expand and simplify using the binomial theorem • (3x – 2y)5
Example 2 Using the binomial theorem, rewrite 1 + 10x2 + 40x4 + 80x6 + 80x8 + 32x10 in the form (a + b)n. n = 5 (6 terms)
General Term of Binomial Expansion The general in the expansion of (a + b)nis
Example 3 Use Pascal’s Identity to write an expression for n = 47 r = 14
Example 4 Consider the expansion of What is the constant term? or We want an-rbr = x0 8 – 3r = 0 r must be a whole number, so there is no constant term!