Search our library of Maths questions

Top answers

Maths

All levels

Find the coordinate of the stationary point on the curve y = 2x^2 + 4x - 5.

The important point in the question is the term 'stationary point'. This is where the graph of y will 'flattern out'. If we look at this graph, we can say that the gradient is equal to 0 at this point. Th...

Answered by Serkan M. • Maths tutor

4602 Views

write (x+2)(x+3)(x+5) in the form ax^3+bx^2+cx+d

First take (x+2)(x+3) and expand to get x²+3x+2x+6, which can be simplified to equal x²+5x+6.Then mutiple x²+5x+6 by (x+5). This will give you x³+5x²

Answered by Cora H. • Maths tutor

3082 Views

Using the identity cos(A+B)= cosAcosB-sinAsinB, prove that cos2A=1-2sin^2A.

Use cos(A+B)=cosAcosB-sinAsinB and let A=B so cos(A+A)=cosAcosA-sinAsinA this means cos(2A)=cos²A-sin²A and since cos²A+sin²A=1, cos²A=1-sin²

Answered by Rebecca F. • Maths tutor

20086 Views

A curve has the equation: x^3 - x - y^3 - 20 = 0. Find dy/dx in terms of x and y.

x³ - x - y³ - 20 = 0 Find dy/dx. Differentiate with respect to x.
3x² - 1 - 3y²(dy/dx) = 0Therefore: dy/dx = (3x

Answered by Karishma P. • Maths tutor

3229 Views

Alex designs a game for people to play, using two fair five-sided spinners. A person wins the game when both spinners land on the same letter. People pay 40p for each game they play. The prize for a win in £1. Is she likely to raise money?

In order to raise money, we need the average number of wins to be smaller than the average number of losses by at least a factor of 0.4.
The average number of wins will be the number of games multipl...

Answered by Megan L. • Maths tutor

2798 Views