Top answers

Factorise x^2+2x-8

Firstly, note the general equation for a quadratic: ax^2+bx+c. We can see that in the above equation, a=1, b=2 and c=-8. When factorising we have to consider the product ac and b. ac=1(-8)=-8 and b=2. Now th...
KT
Answered by Katie T. • Maths tutor
9456 Views

What are the cases in German?

The cases help us to identify the noun's role in the sentence and make the article of the noun change depending on the case, gender and number. Nominative is the subject of the sentence (who's doing the acti...
IH
Answered by Imogen H. • German tutor
3339 Views

What is gravitational potential energy? Why is it negative?

We define gravitational potential as: the work done to bring a small "test" mass from infinity to a point. But what does this truly mean? The "work done" is simply the energy we need to p...
AS
Answered by Alexander S. • Physics tutor
92304 Views

Please explain William the Conqueror's reasons for invading England in 1066?

The death of Edward the Confessor in early 1066 would prompt one of the most significant military campaigns in English history, the invasion of William of Conqueror. The reasons for William's invasion of Eng...
NM
Answered by Nicholas M. • History tutor
32346 Views

Using the Trapezium rule with four ordinates (three strips), estimate to 4 significant figures the integral from 1 to 4 of (x^3+12)/4sqrt(x). Calculate the exact value of this integral, comparing it with your estimate. How could the estimate be improved?

Taking the value at the ordinates f(1) = 13/4, f(2) = 20/4sqrt(2), f(3) = 39/4sqrt(3), f(4) = 9.5 Then the trapezium rule states the integral is approximately 1/2 * [f(1) + 2f(2) + 2f(3) + f(4)], which (usin...
RM
Answered by Robert M. • Maths tutor
8432 Views