Top answers

Find the first three terms in the binomial expansion of (8-9x)^(2/3) in ascending powers of x

Rewrite (8-9x)^(2/3) as (8(1-(9/8)x)^(2/3)=4(1-(9/8)x)^(2/3). Now apply the C4 binomial formula in the formula booklet, so: 4(1 - ((9/8)x)^(2/3)= 4[ 1 + (2/3)*((-9/8)x) + (2/3)((-9/8)x)^2 .....]= 4[ 1 - (3/4...
AR
Answered by Anthony R. • Maths tutor
12931 Views

IB exam question: Let p(x)=2x^5+x^4–26x^3–13x^2+72x+36, x∈R. For the polynomial equation p (x) = 0 , state (i) the sum of the roots; (ii) the product of the roots.

p(x) = 2x 5 + x 4 – 26x 3 – 13x 2 + 72x + 36 i) obtain the sum by using vieta's fomula: for p(x) the sum is hence -b/a hence, sum = -1/2 ii) obtain the product by using the fomula -f/a. This is because the p...
NM
Answered by Niccolo M. • Maths tutor
8234 Views

The curve has the equation y= (x^3)/(2x-1). Find dy/dx.

To differentiate a function with respect to (wrt) x you multiply the function by the power and then lower the power by one. For example, if f(x)=x^3, then to differentiate you multiply the function by 3 (the...
PC
Answered by Poppy C. • Maths tutor
6259 Views

How do you know when to add probabilities together and when to multiply them together

A probability that an event occurs will always range between 0 and 1. If you want to know the probability of two events both happening you would multiply them together. For exampke what is the probability I ...
PS
Answered by Priyen S. • Maths tutor
6219 Views

A 4kg bag of rice costs £3.20 and a 6kg bag of rice costs £5.80. Which bag of rice is the best value for money? Show all your working.

To work out which bag is best value for money you have to work out the price of each bag per kg. To do this you must divide the price of the bag by the number of kg's it weighs. I.e. 3.20/4 = 80p per kg, 5.8...
YN
Answered by Yasha N. • Maths tutor
4942 Views