4. Binomial Expansion

Question 1

nCr simplified formula

Answer 1

n(n-1)(n-2)…(n-r)/r!

Question 2

(1 + ax)^n binomial

Answer 2

1 + nax + n(n-1)/2! (ax)^2 + n(n-1)(n-2)/3! (ax)^3 + …

Question 3

Estimating where you can’t get what you are estimating by a substitution

Answer 3

Plug into your calculator and set equal to the estimate then rearrange for what you need to estimate

Question 4

(a+bx)^n method

Answer 4

(a(1 + b/a(x)))^n

a^n X (1 + b/a (x))^n

Question 5

Fractions of binomial functions

Answer 5

Find each separately and multiply

Question 6

Where is (1+ax)^n binomial valid

Answer 6

|ax|< 1