Chapter 8 The Binomial Expansion Flashcards
How is Pascal’s triangle formed?
By adding adjacent pairs of numbers to find the numbers on the next row
What does the (n+1)th row of Pascal’s triangle give the coefficients for?
The expansion of (a+b)^n
How can you find entries in Pascal’s triangle quickly?
Use the nCr button on the calculator
What is the formula for nCr?
n! / r!(n-r)!
How do you find the rth entry in the nth row of Pascal’s triangle?
(n-1)C(r-1)
What is the binomial expansion of (a+b)^n?
a^n + nC1 x a^n-1 x b + nC2 x a^n-2 x b^2 + … + b^n
What is the general term in the expansion of (a+b)^n?
nCr x a^n-r x b^r
How do you find an approximation for a binomial expansion?
Ignore larger powers of x
When can you find an approximation for a binomial expansion?
When the value of x is less than 1