Top answers

Maths
A Level

The probability distribution of the random variable X is given by the formula P(X = x) = 0.09+0.01x^2 for x= 1,2,3,4,5 ). Find E(X).

The expected value of a discrete variable is defined as:

E(X) = ∑x*P(X=x) (for all possible values of x, in this case x = {1,2,3,4,5} ) 

(next, we will expand the summation and substitute in...

RH
Answered by Robin H. Maths tutor
7433 Views

Integrate cos(2x)

The intergral for cosx is sinx, but '2x' must be considered.

When differentiating a sinx/cosx function, the '2x' would be differentiated separately

and placed in the front (multipling). So w...

GO
Answered by Gold O. Maths tutor
18124 Views

How do you solve the equation e^2x - 2e^x - 3 = 0 ?

This is a 'quadratic in e^x'. The easiest way to recognise this when starting problems like this is to let y=e^x. As you practice problems like this, you will find yourself moving away from this step. But...

LC
Answered by Lewis C. Maths tutor
14779 Views

How do you simplify something of the form Acos(x) + Bsin(x) ?

This sort of question is quite common, and a little bit complicated, so the explanation is quite long! But it's a great one to understand. There are a few tricks you need to know to be able to do...

JM
Answered by Jack M. Maths tutor
14363 Views

f(x) = (4x + 1)/(x - 2) with x > 2. Find a value for 'x' such that f'(x) (first derivative of f(x) with respect to x) is equal to -1.

  1. Re-write f(x)  using indicies, so that the use of the product rule becomes more clear => f(x) = (4x + 1) *(x - 2)^-1 where ^ means 'raised to the power of' and * means 'multiplied by'.

    ZS
    Answered by Zak S. Maths tutor
    4502 Views

We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning