Top answers

How do I work out how a number is written in fraction form, if it is a reoccurring decimal?

If I have a reocurring decimal I use a special trick to work it out as a fraction. The trick is to try and cancel out the reocurring bit by multiplying by 10 several times and then using subtraction. E.g. 7....
JD
Answered by Jasmin D. • Maths tutor
3616 Views

Solve the equation x^2-9x+20

Multiples that equal 20: 1 and 20, 2 and 10, 4 and 5Which of these multiples add/subtract to give -9?= -4 and -5Therefore answer is:(x-4)(x-5)=0x= 4 or x= 5
MC
Answered by Megan C. • Maths tutor
4343 Views

The angle of elevation to the top of a tree is 63 degrees. Given that the distance to the tree is 15 m and your height is 1.6 m, how tall is the tree?

Drawing a diagram for this would show that the height of the tree above us is given by tan(63)*15, so the total height is this added to 1.6 m. This gives a height of 31 m.
LV
Answered by Lucy V. • Maths tutor
3977 Views

(C3 question). Find an expression for all stationary points on the curve y=sin(x)cos(x). How many such points are there and why?

Stationary points are points at which the gradient of the curve is zero. The gradient is given by dy/dx so we start by computing this using product rule to give us dy/dx=-sin 2 x+cos 2 x. Notice that this is...
TG
Answered by Tristan G. • Maths tutor
6471 Views

(FP3 question). Integrate 1/sqrt(3-4x-x^2).

There are two stages to this integral. Stage 1: Notice that there is a quadratic inside a square root in the denominator. We wish to look for a substitution which will reduce this problem to a known integral...
TG
Answered by Tristan G. • Maths tutor
6774 Views