Search our library of A Level questions

Top answers

All subjects

A Level

How did jazz influence mainstream music in Europe and America? [How to approach and introduce this question]

Conceptions of jazz culture and music that began to develop at the very beginning of the twentieth century both in the US and in Europe have had significant repercussions for directions taken not just in ...

Answered by Freddie R. • Music tutor

3688 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

21914 Views

Describe the events that occur at synaptic junction that result in an action potential in the post synaptic membrane.

An action potential arrives at the pre synaptic membrane which initiates the opening of Ca2+ channels. The influx of Ca2+ ions will cause vesicles containing neurotransmitters to fuse with the pre-synapti...

Answered by Samantha B. • Biology tutor

3813 Views

A rectangular hyperbola has parametric equations x = 4t, y = 4/t , (z non 0). Points P and Q on this hyperbola have parameters t = 1/4 and t = 2. Find the equation of the line l which passes through the origin and is perpendicular to the line PQ.

Since we are told that the line l is perpendicular to the line PQ, we first need to find out the gradient of PQ.
To do this, it is easiest to find out the co-ordinates of points P and Q in terms of...

Answered by Zelie E. • Further Mathematics tutor

2585 Views

How can I improve my grade when writing a psychology essay?

One of the first things you can do before even trying to start an essay is looking at the marking criteria to see what the marker wants from you and what your essay needs to show. For example, in an AQA m...

Answered by Kelly L. • Psychology tutor

3669 Views