Binomial expansion

Question 1

When answering a question on binomial expansion what should you remember to do?

Answer 1

To use brackets
To be careful of negatives

Tip: the sum of the two powers should be the same as the original power

Question 2

How many terms will (a+b)^3 have?

Answer 2

4

Question 3

What are binomials used for?

Answer 3

To estimate

Question 4

If the question is to expand (-4-kx)^4 , what is a,b and c?

Answer 4

a=-4 b=-kx c=4

Question 5

What formula should we use to find the expansion of (a+bx)^n where n is a natural number (NOT A FRACTION or NEGATIVE NUMBER)

Answer 5

a^n +(n/1)a^(n-1)b + (n/2)a^(n-2)b^2 +…

Question 6

What formula should we use to find the formula of the binomial expansion (1+x)^n where n IS a FRACTION or NEGATIVE number?

Answer 6

1 +nx + n(n-1)/2! x x^2 + …

Question 7

Why does the binomial expansion 1 +nx + n(n-1)/2! x x^2 + … produce an infinite number of terms where as the binomial expansion a^n +(n/1)a^(n-1)b + (n/2)a^(n-2)b^2 +… produces a finite number of terms?

Answer 7

None of the factors in the expansion e.g n(n-1) will =0

Question 8

Values of x must satisfy |x| < 1 for … formula

Answer 8

1 +nx +n(n-1)/2!(x^2) + …