Search our library of A Level questions

Top answers

All subjects

A Level

If y = 1/x^3, find an expression for dy/dx

Write down y = 1/x³ This can be rewritten as y = 1x^-3 or just y = x^-3as if the x is on the bottom of the fraction, it can be rewritten with a negative version of the powe...

Answered by Pete B. • Maths tutor

6484 Views

Prove the identity (sin2x)/(1+(tanx)^2) = 2sinx(cosx)^3

For a proof like this, I like to start with the more difficult-looking side, and aim to end up with the expression on the other side. Starting with the left hand side, the first thing to change is the sin...

Answered by Alice C. • Maths tutor

9309 Views

Consider and evaluate the ways in which Sylvia Plath, in her poem 'Nick and the Candlestick' (1962) presents an individual who is motivated by selfishness.

Sylvia Plath in her poem ‘Nick and the Candlestick’ (1962) presents an individual motivated by selfishness, someone who relies on their new born baby to meet their personal needs. For example, in the poem...

Answered by Polly H. • English Literature tutor

4874 Views

The line l1 has equation 4y - 3x = 10. Line l2 passes through points (5, -1) and (-1, 8). Determine whether the lines l1 and l2 are parallel, perpendicular or neither.

To determine the answer the gradient of both lines must be found. To find the gradient of line l1 the equation can be rewritten in the form y = mx + c. 4y - 3x = 10 so y = 3/4 x + 5/2. From this equation ...

Answered by Rosie M. • Maths tutor

15899 Views

How may nitrate from fertiliser entering lakes cause the death of fish in fresh water?

The addition of excess nitrate to the freshwater body causes algal bloom on the surface, blocking sunlight. This reduces the photosynthetic activity of submerged plants, causing them to die. Subsequently,...

Answered by Cocoa M. • Biology tutor

2846 Views