Top answers

GCSE: I don't understand how to rationalise denominators

First, I would make sure the pupil understands why rationalising fractions is necessary. Then I would acquaint them with the relevant vocabulary so they can express their thought process better and understan...
CA
Answered by Cora A. • Maths tutor
4181 Views

How to do add or subtraction fractions?

A fraction a/b consists of a numerator (the part above the bar, a in this example) and a denominator (the part below the bar, b here). In order to add or subtract fractions, we need to make sure the denomina...
ML
Answered by Michelle L. • Maths tutor
4463 Views

Given that y > 0, find ∫((3y - 4)/y(3y + 2)) dy (taken from the Edexcel C4 2016 paper)

This can't be integrated directly as y appears in the numerator and denominator. This is an indication that you must integrate by parts. A/y + B/(3y+2) = (3y - 4)/y(3y + 2) A and B must be found. Multiply by...
SS
Answered by Saskia S. • Maths tutor
12183 Views

A rectangle has an area of 20 cm^2.  Its length and width are enlarged by scale factor 3.  Find the area of the enlarged rectangle.

Area Scale Factor = (Scale Factor) 2 If the scale factor is 3 then: ASF = 3 2 ASF = 9 Area of enlarged rectangle = 20x9 Area of enlarged rectangle = 180cm 2
MU
Answered by Melanie U. • Maths tutor
4927 Views

Rearrange the formula: m = 2ab/4c+b to make b the subject

m = 2ab/4c+b [times both sides by (4c+b)] m(4c+b) = 2ab (expand the bracket) 4cm+bm = 2ab (take away bm from both sides) 4cm = 2ab - bm (take out b as the common factor) 4cm = b(2a-m) [divide both sides by (...
MU
Answered by Melanie U. • Maths tutor
6369 Views